intercontinental and transoceanic fixed links

In 1890 William Gilpin first proposed to connect all the continents by land via the Cosmopolitan Railway. Significant elements of that proposal, such as the English Channel Tunnel, have been constructed since that era. However, the improvement of the global shipping industry and advent of international air travel has reduced the demand for many intercontinental land connections.

{{Main|Channel Tunnel}}

There is no public highway connection between Great Britain and the European mainland; only a rail connection, the Channel Tunnel.

A cross channel tunnel was first proposed in 1802 and construction actually started in 1881 before being abandoned. Roll-on/roll-off ferry services provided links across the channel for vehicles.

A road tunnel was proposed in 1979, but not considered viable. Construction of the Channel Tunnel started in 1988 and the tunnel opened in 1994. Automobiles and lorries/transport trucks are loaded onto the Eurotunnel Shuttle's enclosed railway cars (similar to auto rack/motorail railway cars) for the trip through the tunnel. A service road tunnel runs the entire length of the crossing, but is closed to general use and used only during emergencies and for maintenance. Cyclists – both amateur and professional – have crossed the channel via the tunnel on special occasions.{{Cite web |date=2018-10-11 |title=Children in Need Rickshaw Challenge to travel through Kent |url=https://www.kentonline.co.uk/weald/news/children-in-need-rickshaw-challenge-to-travel-through-kent-191327/ |access-date=2024-01-19 |website=Kent Online |language=en}}

There have been proposals at various times for a second channel tunnel of some kind.{{Cite web|url=http://news.bbc.co.uk/2/shared/spl/hi/uk/04/channel_tunnel/html/fantasy.stm|title=BBC News}}

Various ferry services link Ireland to Britain and France. A number of options for an Irish Sea fixed crossing have been proposed over the years, but none are currently under serious consideration.{{citation needed|date=December 2020}} Additionally, there was a short-lived proposal for an underground roundabout beneath the Isle of Man, connecting tunnels to Ireland, Scotland, and two to England.{{Cite magazine |last=Moore |first=Catherine |date=2021-02-23 |title=Underground roundabout beneath Isle of Man proposed to link three Irish Sea tunnels |url=https://www.newcivilengineer.com/latest/underground-roundabout-beneath-isle-of-man-proposed-to-link-three-irish-sea-tunnels-23-02-2021/ |access-date=2023-05-17 |magazine=New Civil Engineer |language=en}} Another proposal was for an additional route from Scotland to the Isle of Man.{{cite web |date=26 January 2018 |title=Architect proposes IoM-Scotland road-link |url=https://www.manxradio.com/news/isle-of-man-news/architect-proposes-iom-scotland-road-link/ |publisher=Manx Radio}}

File:Irish Sea tunnels.jpg]]

In July 2009, the States of Jersey were considering the feasibility of building a {{convert|14|mi|km|adj=on}} tunnel between Jersey (a British Crown dependency) and Lower Normandy in France.{{cite news |date=14 July 2009 |title=Jersey-France tunnel plan talks |url=http://news.bbc.co.uk/1/hi/world/europe/jersey/8149314.stm |access-date=24 June 2018 |via=news.bbc.co.uk}}{{cite web |title=Bridge to France: Study next year? |url=http://jerseyeveningpost.com/news/2008/10/18/bridge-to-france-study-next-year/ |access-date=24 June 2018 |website=jerseyeveningpost.com|date=18 October 2008 }}{{cite web |title=Un projet de tunnel pour relier Jersey à la Manche |date=9 July 2009 |url=http://www.ouest-france.fr/un-projet-de-tunnel-pour-relier-jersey-la-manche-524626 |access-date=24 June 2018}} There was a revival of the idea in 2018{{cite web |title=jersey-guernsey-france tunnel proposed |date=17 July 2019 |url=https://jerseyeveningpost.com/news/2019/07/17/jersey-guernsey-france-tunnel-proposed/}} and 2021.{{cite web |title=renewed calls for channel island tunnel after faroe islands success |url=https://www.itv.com/news/channel/2021-01-12/renewed-calls-for-channel-island-tunnel-after-faroe-islands-success}} It was reported in the local media that a link between Jersey and the neighbouring island of Guernsey would cost £2.6 billion.{{cite web |title=tunnel-to-jersey-to-cost-26bn-and-take-decade |date=24 January 2020 |url=https://guernseypress.com/news/2020/01/24/tunnel-to-jersey-to-cost-26bn-and-take-decade}}

The Crimean Bridge is a pair of parallel bridges constructed by the Russian Federation following the annexation of Crimea, to span the Kerch Strait between the Taman Peninsula of Krasnodar Krai and the Kerch Peninsula of Crimea. The bridge complex provides for both vehicular traffic and for rail. During the Russian invasion of Ukraine, the bridge has been attacked or damaged on three occasions: 8 October 2022, 17 July 2023 and 12 August 2023.{{Cite news |last=Boffey |first=Daniel |date=2023-08-12 |title=Ukraine fires missiles at Kerch Bridge connecting Crimea to Russia |url=https://www.theguardian.com/world/2023/aug/12/ukraine-fires-missiles-at-kerch-bridge-connecting-crimea-to-russia |access-date=2024-01-19 |work=The Guardian |language=en-GB |issn=0261-3077}} As of August 2023, the bridge reopened at a limited capacity.{{Cite web |date=2023-08-17 |title=Crimean bridge operating in limited mode |url=https://news.yahoo.com/crimean-bridge-operating-limited-mode-060247076.html |access-date=2024-01-19 |website=Yahoo News |language=en-US}}

The Øresund Bridge links southern Sweden to the Danish island of Zealand. Zealand is linked to the Danish mainland and the rest of Europe by the Great Belt Fixed Link. Most travellers between Sweden and Germany, both by road and train, use the {{convert|160|km|mi|abbr=on}} shorter route with a ferry over the Fehmarn Belt southwestwards towards Hamburg or southwards to Rostock. The Fehmarn Belt Fixed Link is planned to be opened in 2029. A Gedser-Rostock Bridge is also under consideration but has been put back as the Fehmarn Belt crossing is now under construction. Proposals also exist for a fixed link from Rügen to southern Sweden, linking Berlin and the Øresund region.

Ferry services link Sweden to Finland via Åland. There are proposals of fixed links between Sweden and Finland. A tunnel could be built between Sweden and Åland, about {{cvt|50|km|sigfig=1}} long, and {{cvt|100-200|m|}} deep, with the lowest depth around Märket, a little detour. The area between Åland and Finland is shallow with many islands, able to be connected with bridges - some of which already exist. Between Umeå and Vaasa further north, there is a proposal to build the Kvarken Bridge, a series of bridges, the longest {{cvt|26|km|}}, in total {{cvt|40|km|}}. None of these proposals have been seriously investigated.

Ferry services link Finland to Estonia as well as overground rail and road routes via Saint Petersburg in Russia. Rail Baltica is a proposal for a rail link from Finland to Estonia, Latvia, Lithuania and Poland, bypassing Russia via a Helsinki to Tallinn Tunnel. The gulf has heavy ferry traffic, and the port of Helsinki has the largest number of international passengers of any port in Europe, and most travel to Tallinn or back. Finland and Estonia share close linguistic, cultural, economic and historical ties and proponents of what they call "Talsinki" (a portmanteau of the names of the two capitals) point to the Øresund region as an example of a cross-national metropolitan area linked by an underwater bridge-tunnel. A combination of a Finland to Estonia and a Finland to Sweden fixed link would reduce the need for ferries on the route the MS Estonia was on when it sank in 1994 causing a loss of 852 lives, the biggest peacetime maritime disaster in the Baltic.

The Strait of Messina has a busy ferry traffic. The Strait of Messina Bridge is planned{{citation needed|date=July 2021}}, but the construction date has been postponed several times.

There is a project to link Elba with mainland Italy (through Piombino in Tuscany) crossing the Piombino Channel in a Road Tunnel of 16 km.{{Cite web |title=Tuscany Tunnel – Strategy part of Cacelli Group Ltd |url=https://strategy.cacelli.com/elba-tunnel/ |access-date=2023-05-19 |language=en-US}} The feasibility project was launched by the Cacelli Partners Ltd of Riccardo Cacelli, in collaboration with the Adu London studio of the architect David Ulivagnoli.{{Cite web |title=Elba Tunnel, terminato il progetto di fattibilità |url=https://www.quinewselba.it/londra-elba-tunnel-galleria-sotterranea-fra-piombino-ed-elba.htm |access-date=2023-05-19 |website=www.quinewselba.it |language=it}}{{Cite web |last=MEDICI |first=ROBERTO |title=Un tunnel per collegare l'Elba al Piombino: ora c'è qualcosa di più di una semplice idea - Cronaca |url=https://www.lanazione.it/cronaca/elba-tunnel-1.4406899 |access-date=2023-05-19 |website=La Nazione |date=24 January 2019 |language=it}}

There is a project of an underwater tunnel that will link Palau (in Sardinia) with the island of La Maddalena, crossing a 3 km stretch of sea.{{Cite web |title=Tunnel sottomarino tra La Maddalena e Palau: c'è il progetto, sui social è "battaglia" |url=https://www.today.it/ambiente/tunnel-sottomarino-palau-maddalena.html |access-date=2023-05-19 |website=Today |language=it}}{{Cite web |date=2017-05-25 |title=Un tunnel sottomarino tra la Maddalena e Palau. Sui social mobilitazione per il sì |url=https://www.repubblica.it/cronaca/2017/05/25/news/un_tunnel_sottomarino_tra_la_maddalena_e_palau_sui_social_mobilitazione_per_il_si_-166329046/ |access-date=2023-05-19 |website=la Repubblica |language=it}}

The has been interest from Hyperloop One in using Hyperloop to connect the islands.{{Cite web |date=2017-01-13 |title=Hyperloop: un progetto per collegare Corsica e Sardegna con un treno a 1.200 km/h – Corsica Oggi |url=https://www.corsicaoggi.com/sito/hyperloop-un-progetto-collegare-corsica-sardegna-un-treno-1-200-kmh/ |access-date=2023-05-19 |language=it-IT}}{{Cite web |title=Hyperloop One: c'è un progetto per collegare Corsica e Sardegna |url=https://www.dday.it/redazione/23463/hyperloop-one-ce-un-progetto-per-collegare-corsica-e-sardegna |access-date=2023-05-19 |website=DDay.it |language=Italian}}

There were proposals to build a railway and highway bridge over the Adriatic sea to connect Italy and Croatia, from Ancona to Zadar following a 120 km route. The idea was presented by the Roman architect Giorgio De Romanis, and also called for the creation of a special company "Il ponte sull'Adriatico Srl". The bridge would be suspended above the sea at a height of between 30 and 70 meters, and would also allow the laying of pipes for water, oil and gas, as well as the accommodation of telecommunication cables.{{Cite web |last=s.p.a |first=edilportale com |title=Un ponte sull'Adriatico per collegare Italia e Croazia |url=https://www.archiportale.com/news/2005/04/lavori-pubblici/un-ponte-sull-adriatico-per-collegare-italia-e-croazia_6381_11.html |access-date=2023-05-19 |website=Archiportale}}{{Cite web |date=2016-12-22 |title=Un Ponte sull'Adriatico e la Nuova Via della Seta: una connessione possibile? |url=https://www.cese-m.eu/cesem/2016/12/un-ponte-sulladriatico-e-la-nuova-via-della-seta-una-connessione-possibile/ |access-date=2023-05-19 |website=Centro Studi Eurasia e Mediterraneo |language=it-IT}} The idea received the support of the ex-governor of the Marche, Gian Mario Spacca. Some sources considered the project as being more realistic than a bridge between Calabria and Sicily{{Cite web |last=www.altrogiornalemarche.it |date=2016-10-19 |title=Da Ancona a Zara il sogno del Ponte sull'Adriatico |url=https://www.altrogiornalemarche.it/2016/10/ancona-zara-sogno-del-ponte-sulladriatico/ |access-date=2023-05-19 |website=AltrogiornaleMarche |language=it-IT}}

{{Main|Vlora-Otranto Tunnel}}

The Vlora-Otranto Tunnel is a proposed undersea tunnel that aims to connect Vlorë, in Albania, with Otranto, in Italy, across the Strait of Otranto, a narrow strip of water that separates the Adriatic Sea from the Ionian Sea and is about 71 kilometers (44 miles) wide at its narrowest point.

The Boknafjord tunnel (main part of the Rogfast project) is under construction and will in 2033 be the world's longest and deepest undersea road tunnel, {{convert|26.7|km|ft}} long and reach {{convert|392|m|ft}} under sea level. It will connect the island of Bokn with the mainland at Stavanger under the open Bokna Fjord.

Tunnels and bridges are an important part of the Faroe Islands transportation network. The longest proposed one is the 25 km Suðuroyartunnilin (the Suðuroy Tunnel).

Vestmannaeyjagöng is a proposed undersea tunnel linking the archipelago Vestmannaeyjar to the Icelandic mainland.

{{Main|Strait of Gibraltar crossing}}

The Gibraltar Tunnel is proposed to be a rail tunnel linking Africa and Europe. A tunnel would likely be an electrified rail tunnel with car shuttles due to the depth of the Strait of Gibraltar (up to {{convert|900|m}}) and the length of the tunnel making it a great challenge to remove vehicle exhaust. Similar considerations led to the Channel Tunnel linking the UK and France not being a highway tunnel. There have also been proposals for a bridge over the strait, although ship traffic would complicate this solution. Car ferries currently operate across the strait.

The proposed Strait of Sicily Tunnel would link Sicily to Tunisia. Together with the proposed Strait of Messina Bridge from Sicily to Italy this would provide a fixed link between Italy and Tunisia.

The Turkish Straits are the channel between European Turkey and Asian Turkey and consist of the (from south to north) the Dardanelles, the Sea of Marmara and the Bosphorus.[https://www.britannica.com/place/Asia Asia] — Encyclopædia Britannica[http://www.britannica.com/EBchecked/topic/195686/Europe Europe] — Encyclopædia BritannicaЕвропа // Большая советская энциклопедия : [в 30 т.] / гл. ред. А. М. Прохоров. — 3-е изд. — М. : Советская энциклопедия, 1969—1978

File:Rumeli hisari.jpg (1988) as seen from the Rumelian Castle (1452)]]

File:Bosphorus Bridge-1.jpg (1973)]]

Three suspension bridges cross the Bosphorus. The first of these, the Bosphorus Bridge, is {{convert|1074|m|ft|0|abbr=on}} long and was completed in 1973. The second, named Fatih Sultan Mehmet (Bosporus II) Bridge, is {{convert|1090|m|ft|0|abbr=on}} long, and was completed in 1988 about {{convert|5|km|mi|0|abbr=on}} north of the first bridge. The Bosphorus Bridge forms part of the O1 Motorway, while the Fatih Sultan Mehmet Bridge forms part of the Trans-European Motorway.

Construction of a third suspension bridge, the Yavuz Sultan Selim Bridge, began on May 29, 2013;{{cite web|url=http://www.roadtraffic-technology.com/projects/yavuz-sultan-selim-bridge-istanbul |title=Yavuz Sultan Selim Bridge, Istanbul |website=roadtraffic-technology.com |access-date=August 29, 2016}} it was opened to traffic on August 26, 2016.*{{cite web|url=http://www.trtworld.com/turkey/3rd-bosphorus-bridge-opening-ceremony-172455|title=3rd Bosphorus bridge opening ceremony|publisher=TRT World|date=August 25, 2016|url-status=dead|archive-url=https://web.archive.org/web/20160828093449/http://www.trtworld.com/turkey/3rd-bosphorus-bridge-opening-ceremony-172455|archive-date=August 28, 2016}}

• {{cite web |url=http://www.dailysabah.com/money/2016/08/26/istanbuls-mega-project-yavuz-sultan-selim-bridge-to-open-in-large-ceremony |title=Istanbul's mega project Yavuz Sultan Selim Bridge to open in large ceremony |newspaper=The Daily Sabah |date=August 25, 2016 |access-date=August 29, 2016 |archive-date=February 28, 2020 |archive-url=https://web.archive.org/web/20200228181609/https://www.dailysabah.com/money/2016/08/26/istanbuls-mega-project-yavuz-sultan-selim-bridge-to-open-in-large-ceremony |url-status=dead }} The bridge was built near the northern end of the Bosporus, between the villages of Garipçe on the European side and Poyrazköy on the Asian side.{{cite web|url=http://www.aa.com.tr/en/turkey-unveils-route-for-istanbuls-third-bridge.html |title=Turkey Unveils Route for Istanbul's Third Bridge |publisher=Anatolian Agency |date=29 April 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100619081305/http://www.aa.com.tr/en/turkey-unveils-route-for-istanbuls-third-bridge.html |archive-date=19 June 2010 }} It is part of the "Northern Marmara Motorway", which will be further integrated with the existing Black Sea Coastal Highway, and will allow transit traffic to bypass city traffic.

The Marmaray project, featuring a {{convert|13.7|km|mi|abbr=on}} long undersea railway tunnel, opened on 29 October 2013.{{cite news |title=Turkey's Bosporus tunnel to open sub-sea Asia link |publisher=BBC News |date=29 October 2013 |url=https://www.bbc.co.uk/news/world-europe-24721779}} Approximately {{convert|1400|m|ft|0|abbr=on}} of the tunnel runs under the strait, at a depth of about {{convert|55|m|ft|0|abbr=on}}.

An undersea water supply tunnel with a length of {{convert|5551|m|ft|abbr=on}}, named the Bosporus Water Tunnel, was constructed in 2012 to transfer water from the Melen Creek in Düzce Province (to the east of the Bosporus strait, in northwestern Anatolia) to the European side of Istanbul, a distance of {{convert|185|km|mi|abbr=on}}.[http://www.cnnturk.com/2012/turkiye/05/21/melen.hatti.bogazi.gecti/661848.0/index.html CNN Türk: "Melen hattı Boğaz'ı geçti" (21-05-2012)]{{cite news|url=http://www.sabah.com.tr/Ekonomi/2012/05/19/melen-bogazi-geciyor|newspaper=Sabah Ekonomi|title=Melen Boğaz'ı geçiyor|author=Nayır, Mehmet|date=2012-05-19|language=tr|access-date=2012-06-11}}

The Eurasia Tunnel is a road tunnel between Kazlicesme and Goztepe, which began construction in February 2011 and opened to traffic on 21 December 2016. The Great Istanbul Tunnel, a proposed undersea road and railway tunnel, will connect Şişli and Beykoz districts.

The Çanakkale 1915 Bridge opened in 2022, crossing the strait between the cities of Gelibolu and Lapseki.

The Mubarak Peace Bridge, also known as the Egyptian-Japanese Friendship Bridge, Al Salam Bridge, or Al Salam Peace Bridge, is a road bridge crossing the Suez Canal at El-Qantara, whose name means "the bridge" in Egyptian Arabic. The bridge links the continents of Africa and Asia.

The Saudi–Egypt Causeway is a proposal for a causeway and bridge between the Sinai Peninsula in Egypt and the northern part of Saudi Arabia. This would provide a direct road route between Egypt and Saudi Arabia without going through Israel or Jordan. A causeway faces considerable political hurdles as the disruption of Israeli shipping access to the Red Sea was seen as a casus belli by Israel ahead of the Six-Day War. There is a car ferry between Safaga, Egypt and Duba, Saudi Arabia. The two uninhabited islands in the strait (Tiran island and Sanafir island), which might be used for a bridge, tunnel or causeway, were disputed between Egypt and Saudi Arabia until President Abdel Fatah al-Sisi of Egypt officially ceded them to Saudi Arabia in 2016/2017.{{cite news |url=https://www.reuters.com/article/us-egypt-saudi-islands-idUSKBN19F0KE |title=Egypt's Sisi ratifies deal ceding Red Sea islands to Saudi Arabia |work=Reuters |date=24 June 2017}}{{Cite web|url=https://www.middleeastmonitor.com/20160410-egypt-cedes-two-red-sea-islands-to-saudi-arabia/|title=Egypt cedes two Red Sea islands to Saudi Arabia|date=10 April 2016}} The potential construction of a fixed link was cited in some media reports as contributing to the cession.{{cite news |url=https://www.wsj.com/articles/egypt-parliament-cedes-islands-to-saudi-arabia-risking-backlash-1497465791 |title=Egypt Parliament Cedes Islands to Saudi Arabia Risking Backlash |newspaper=Wall Street Journal |date=14 June 2017 |last1=Kholaif |first1=Dahlia}}{{Cite web|url=https://www.middleeasteye.net/opinion/why-saudi-arabia-decided-reclaim-its-islands-egypt-now|title=Why Saudi Arabia decided to reclaim its islands from Egypt now}}

The Bridge of the Horns is a proposed construction project to build a bridge between the coasts of Djibouti and Yemen across the Bab-el-Mandeb, the strait between the Red Sea and Gulf of Aden.{{Cite web |url=http://enr.construction.com/news/intl/archives/070501.asp |title=Notice-to-Proceed Launches Ambitious Red Sea Crossing – ENR {{!}} McGraw-Hill Construction |access-date=2007-10-02 |archive-date=2009-02-11 |archive-url=https://web.archive.org/web/20090211174736/http://enr.construction.com/news/intl/archives/070501.asp |url-status=dead }} There are no ferry services on this route as of 2018.

Saudi Arabia considers to develop a 440 km tunnel across the Red Sea to link its industrial city of Jazan with Massawa's port in Eritrea. It had the support of Pakistan and the Chinese Belt and Road Initiative.{{Cite web |last=Admin |title=Saudi Arabia considering linking Jazan with Massawa in Eritrea via 440 km tunnel across the Red Sea |url=http://www.madote.com/2018/10/rumor-saudi-arabia-considering-linking.html |access-date=2023-05-17 |website=Madote}}{{Cite web |last=Network |first=Ann Asianews |date=2018-10-30 |title=$6bn bailout package is a big breather for Pakistan |url=https://asianews.network/6bn-bailout-package-is-a-big-breather-for-pakistan/ |access-date=2023-05-17 |website=Asia News Network |language=en-US}}

The Palk Strait bridge proposal between India to Sri Lanka. India Boat Mail train and ferry service provided a train and ferry service from India to Sri Lanka until the First World War. An India–Sri Lanka HVDC Interconnection is under consideration to link the electricity networks of these countries.

Mainland Peninsular Malaysia is linked to Penang Island by two road bridges: the Penang Bridge and the Sultan Abdul Halim Muadzam Shah Bridge (Penang Second Bridge). To the south, it is linked to Singapore Island across the Straits of Johor by the Johor–Singapore Causeway and the Malaysia–Singapore Second Link; the former also carries Malaysia's West Coast Line to the island.

There are proposals to link Johor (in Malaysia) and Riau (in Indonesia), in a Malacca Strait Bridge or underwater tunnel crossing Strait of Malacca and some islands. The longest connection is a 17.5 kilometer. The total length is between 39 and 40 kilometers.{{Cite web |date=2014-03-02 |title=Indonesia and Malaysia explore Johor-Riau undersea tunnel |url=https://www.straitstimes.com/breaking-news/se-asia/story/indonesia-and-malaysia-explore-johor-riau-undersea-tunnel-20140121 |access-date=2023-05-21 |archive-url=https://web.archive.org/web/20140302100314/https://www.straitstimes.com/breaking-news/se-asia/story/indonesia-and-malaysia-explore-johor-riau-undersea-tunnel-20140121 |archive-date=2014-03-02 }}{{Cite web |title=Johor-Riau link on the cards |url=https://www.thestar.com.my/news/nation/2014/01/21/johorriau-link-on-the-cards-175km-undersea-tunnel-to-cost-rm15bil |access-date=2023-05-21 |website=The Star |date=21 January 2014 |language=en}} There's also a proposal of a Singapore Strait crossing linking Singapore with the Riau archipelago of Indonesia, most likely with the island of Batam.{{Cite web |title=Govt urged to consider Batam-Singapore bridge |url=https://www.thejakartapost.com/news/2010/01/05/govt-urged-consider-batamsingapore-bridge.html |access-date=2023-05-21 |website=The Jakarta Post |language=en}} Both projects would link Indonesia (specifically Sumatra and Java islands) to Mainland Asia.

Passenger and vehicle ferries link the various islands of Indonesia, the Philippines, Singapore, Malaysia, and Papua New Guinea.

There are proposals to link Java, the most populated Island of Indonesia, to Sumatra via a proposed Sunda Strait Bridge and from Sumatra to Singapore and/or Malaysia via the Malacca Strait Bridge.

The Guangdong–Hainan Ferry, or the Yuehai Ferry (part of the Guangdong–Hainan Railway) Yue 粤 is the standard Chinese abbreviation for Guangdong, and Hai 海, for Hainan. is a vehicle and train ferry connecting Hainan Island to Guangdong in mainland China. The ferries run across the Qiongzhou Strait, between Zhanjiang, Guangdong and Haikou, Hainan. A road-rail bridge has been proposed.{{Cite web|last=staff|first=Asia Times|date=2019-03-19|title=Mega road-rail bridge planned to connect Hainan|url=https://asiatimes.com/2019/03/mega-road-rail-bridge-planned-to-plug-connect-hainan/|access-date=2020-12-28|website=Asia Times|language=en-US}}

Bohai Strait tunnel project is a proposed connection that would connect the Chinese cities of Yantai and Dalian across the Bohai Strait.{{Cite web |title=China plans undersea tunnel between S. Korea and China - Pulse by Maeil Business News Korea |url=https://pulsenews.co.kr/view.php?year=2015&no=1021787 |access-date=2023-05-20 |website=pulsenews.co.kr |language=ko}}

The Taiwan Strait Tunnel Project is a proposed undersea tunnel to connect Pingtan in the People's Republic of China to Hsinchu in northern Taiwan as part of the G3 Beijing–Taipei Expressway. First proposed in 1996,{{cite web | title = Large basalt reef may make Taiwan Strait Tunnel come true | publisher = Whats On Xiamen | date = 25 November 2009 | url = http://www.whatsonxiamen.com/news8663.html | access-date = 22 February 2012 | archive-url = https://web.archive.org/web/20110312053027/http://www.whatsonxiamen.com/news8663.html | archive-date = 12 March 2011 | url-status = dead }} the project has since been subject to a number of academic discussions and feasibility studies, including by the China Railway Engineering Corporation.{{cite web | title = Discussion on Options of Taiwan Strait Crossing Project and Qiongzhou Strait Crossing Project by 9 Academicians held in Luoyang, China: Several of Them Agree with Tunnel Option | publisher = China Civil Engineering Society | date = 26 April 2011 | url = http://www.cces-tuwb.com/En/shownews.asp?id=408 | access-date = 22 February 2012 | archive-url = https://web.archive.org/web/20130718020525/http://www.cces-tuwb.com/En/shownews.asp?id=408 | archive-date = 18 July 2013 | url-status = dead }} There exist cross strait ferries, both within outlying islands of Taiwan and between the PRC and Taiwan. The political status of Taiwan complicates any such proposal.

The Korean government considered building underwater tunnels with China, the proposed route would be between Incheon-Weihai, being considerate to build an intermediary artificial island in the route of 341 kilometers. Other Korean cities, like Ongjin, Hwaseong and Pyeongtaek, are considered to be part of the routes to China. Also, is part of the Chinese comprehensive development plan for the Bohai area.{{Cite web |date=2010-09-23 |title=Korea considers underwater tunnels to China, Japan |url=https://www.koreaherald.com/view.php?ud=20100923000325 |access-date=2023-05-20 |website=The Korea Herald |language=en}}

The Jeju Undersea Tunnel is a project to connect the South Korean provinces of South Jeolla and Jeju across the Jeju Strait, with intermediate stops at the islands of Bogildo and Chujado.{{Cite news |title=To Jeju, by train? - JEJU WEEKLY |language=ko |url=http://www.jejuweekly.com/news/articleView.html?idxno=486 |access-date=2023-05-20}} The total length of the proposed railway is 167 km, including a 66 km surface interval from Mokpo to Haenam, a 28 km bridge section from Haenam to Bogil Island, and a 73 km stretch from Bogil to Chuja and Jeju Islands.

The Busan–Geoje Fixed Link (or Geoga Bridge) is an 8.2-km bridge-tunnel fixed link that connects the South Korean city of Busan to Geoje Island.{{cite web | url=http://www.deccanherald.com/content/120599/south-koreas-first-bridge-undersea.html | title=South Korea's first bridge-undersea tunnel link opens | date=14 December 2010 }}

The "Korea Japan Friendship Tunnel System" is a proposal for a fixed link from the city of Fukuoka on Kyūshū, Japan, to the port city of Busan in Korea via four islands. The maximum ocean depth in this area is {{convert|146|m|ft|abbr=on}}. Similar proposals have been discussed for decades by Korean and Japanese politicians. A road bridge links Kyūshū to the main Japanese island of Honshu.

The Seikan Tunnel has provided a rail link from the main Japanese Island of Honshu to the northernmost Japanese island of Hokkaido since 1988. The proposed Sakhalin-Hokkaido Tunnel would link Hokkaido to the Russian island of Sakhalin. When combined with the proposed Sakhalin Tunnel between Sakhalin and the Russian Mainland and an extension of the Baikal Amur Mainline this would give a rail link from Japan to Russia and the mainland of Asia.

The Hong Kong–Zhuhai–Macau Bridge links Hong Kong and Macau, and Zhuhai in China. Opened on October 24, 2018, it is the longest fixed crossing in the world.{{citation needed|date=August 2021}}

Shikoku and Kyushu are the only adjacent major Japanese islands not directly connected by a fixed link. Road travel between the two is possible only via Honshu, a detour of up to 600 km.

Since 1995, the Ōita and Ehime prefectures have been jointly conducting research into the technical feasibility of bridges over the Hōyo Strait and conducting basic research into natural and social conditions, and in 1998, in the "Hoyo Kaikyo Bridge Survey Report" it was concluded that the bridge would be technically feasible. The bridge proposed in the report uses a four-span suspension bridge with a central tower height of 376 m, central span length of 3,000 m, and bridge length of about 8,400 m as the main bridge, connecting the Toyo Strait with two bridges, the extension would be about 12.7 km.[http://www.pref.ehime.jp/h12300/hoyoroute/tyou/3/main.html 豊予海峡架橋調査] {{Webarchive|url=https://web.archive.org/web/20150402161534/http://www.pref.ehime.jp/h12300/hoyoroute/tyou/3/main.html |date=2015-04-02 }} 豊予海峡ルート推進協議会事務局 The total project cost is currently estimated to be about 1.3 trillion yen (US$12.1 billion).

The Hoyo Kaikyo Route Promotion Council conducted a survey comparing various crossing technologies (bridges, tunnels) and modes of transportation (automobiles, railways) in 1997, and "Transportation method comparison study report" was published. According to the report, in the case of bridges, road bridges are technically possible, but due to the long span, it is difficult to use them as railway bridges and combined bridges.[http://www.pref.ehime.jp/h12300/hoyoroute/tyou/2tyou/main.html 豊予海峡ルート輸送方式比較検討調査] {{Webarchive|url=https://web.archive.org/web/20150402124835/http://www.pref.ehime.jp/h12300/hoyoroute/tyou/2tyou/main.html |date=2015-04-02 }} 豊予海峡ルート推進協議会事務局

The Qatar Bahrain Causeway was a planned causeway between the two Arab states of Qatar and Bahrain. It was expected that a ferry service would be established between the two countries in 2017.{{cite web| url = https://dohanews.co/first-qatar-to-bahrain-ferry-service-to-launch-next-year/| title = First Qatar to Bahrain ferry service to launch next year - Doha News {{!}} Qatar| date = 14 November 2016}}

Due to the Qatar diplomatic crisis and Bahrain's siding with Saudi Arabia, the bridge is very unlikely ever to be built.

The King Fahd Causeway is a series of bridges and causeways connecting Saudi Arabia and Bahrain. At {{convert|25|km|mi|abbr=on}}, the western terminus of the causeway is the al-Khour neighbourhood of Khobar, Saudi Arabia and the eastern terminus is Al Jasra, Bahrain.

Iran and Qatar (who will take most part of the project's financing) have plans for an underwater tunnel connecting the two countries, being planned to be the longest tunnel in the world (having 190 km).{{Cite web |last=Dudley |first=Dominic |title=Iran Says It Wants To Build The World's Longest Tunnel, Across The Gulf To Qatar |url=https://www.forbes.com/sites/dominicdudley/2022/02/21/iran-says-it-wants-to-build-the-worlds-longest-tunnel-across-the-gulf-to-qatar/ |access-date=2023-05-17 |website=Forbes |language=en}} It would link the Iranian port of Bandar-e Deyr to an unspecified location in Qatar across the Persian Gulf in both road and railway sections; however, a road tunnel is not considered very feasible due to the long distance. It had the support of Iran's Ports and Maritime Organisation managing director, Ali Akbar Safaei, and Iranian President Ebrahim Raisi, who expect the creation of a joint Qatar-Iran committee with the Emir of Qatar, Tamim bin Hamad Al Thani.{{Cite web |last=AsiaNews.it |title=Tehran and Doha to study the feasibility of the longest tunnel in the world |url=https://www.asianews.it/news-en/Tehran-and-Doha-to-study-the-feasibility-of-the-longest-tunnel-in-the-world-55205.html |access-date=2023-05-17 |website=www.asianews.it |language=en}}{{Cite web |last=Mahmood |first=Javed |date=2022-02-21 |title=Qatar and Iran to develop undersea tunnel to link both the countries |url=https://thetruthinternational.com/international/qatar-and-iran-to-develop-undersea-tunnel-to-link-both-the-countries/ |access-date=2023-05-17 |website=The Truth International |language=en-US}}{{Cite web |last=Zahra |date=2022-02-21 |title=Iran, Qatar mull major undersea tunnel project |url=https://theiranproject.com/blog/2022/02/21/iran-qatar-mull-major-undersea-tunnel-project/ |access-date=2023-05-17 |website=The Iran Project |language=en-US}}{{Cite web |date=2022-02-21 |title=Iran, Qatar to sign undersea tunnel project among other major deals |url=https://www.middleeastmonitor.com/20220221-iran-qatar-to-sign-undersea-tunnel-project-among-other-major-deals/ |access-date=2023-05-17 |website=Middle East Monitor |language=en-GB}}{{Cite web |title=Unique underwater tunnel will connect Iran and Qatar {{!}} Bigasia.ru |url=https://bigasia.ru/en/content/news/business/unique-underwater-tunnel-will-connect-iran-and-qatar/ |access-date=2023-05-17 |website=bigasia.ru}} Also, it will create a straight and direct route between Saudi Arabia and Iran.{{Cite web |last=Srivastava |first=Abhishek |date=2022-02-23 |title=As fantastical it may sound! A Saudi-Qatar-Iran trilateral is coming up! |url=https://tfiglobalnews.com/2022/02/23/as-fantastical-it-may-sound-a-saudi-qatar-iran-trilateral-is-coming-up/ |access-date=2023-05-17 |website=TFIGlobal |language=en-US}}

Iran proposed to build an overpass bridge over the strait of Hormuz that will link Iran economically to GCC countries and Yemen through 39 km road link between Oman's Musandam exclave and southern Iran. The idea was having the support of Iranian Ambassador to Oman Ali Akbar Sibeveih.{{Cite web |date=2014-03-06 |title=Oman-Iran plan causeway over Hormuz |url=https://gulfnews.com/world/gulf/oman/oman-iran-plan-causeway-over-hormuz-1.1300526 |access-date=2023-05-17 |website=gulfnews.com |language=en}}{{Cite web |date=2014-03-07 |title=Oman and Iran to build bridge over Hormuz – Middle East Confidential |url=https://me-confidential.com/7930-oman-and-iran-to-build-bridge-over-hormuz.html |access-date=2023-05-17 |language=en-US}}{{Cite web |last=SA@Iran |date=2014-03-06 |title=Oman-Iran plan causeway over Hormuz |url=https://theiranproject.com/blog/2014/03/06/oman-iran-plan-causeway-over-hormuz/ |access-date=2023-05-17 |website=The Iran Project |language=en-US}}

The Persian Gulf Bridge in Qeshm–Bandar Abbas (Iran) will be a {{convert|2.4|km|mi|abbr=on}} long road-rail bridge, connecting Qeshm Island to mainland Iran, from the historic port of Laft to Pahal port in Bandar Abbas (Hormozgan Province). It was proposed to build an undersea tunnel instead of a bridge, but was rejected due to high costs.{{Cite web |url=https://www.realiran.org/persian-gulf-bridge-irans-longest-cross-sea-bridge/ |title=Persian Gulf Bridge: Iran's longest cross-sea bridge |date=February 28, 2022 |access-date=2023-05-17 |archive-date=2023-01-17 |archive-url=https://web.archive.org/web/20230117150905/https://www.realiran.org/persian-gulf-bridge-irans-longest-cross-sea-bridge/ |url-status=dead }}

In 2010, Oman's ruler, Sultan Qaboos bin Saeed, asked the government to plan for the construction of a bridge connecting Masirah Island on Oman's eastern coast to the mainland in a railroad.{{Cite web |date=2010-06-24 |title=Oman considers new bridge project |url=https://www.meed.com/oman-considers-new-bridge-project |access-date=2023-05-17 |website=MEED |language=en}}

The Saudis were exploring two options to build a 400 km tunnel or bridge to link Gwadar (in Pakistan) with Muscat (in Oman) at the mouth of Strait of Hormuz at one end. The objective was to bypass its trade routes (including for oil supplies) with Iran and Qatar, because of the Iran–Saudi Arabia proxy conflict, also to extend the Chinese Belt and Road Initiative.

A {{convert|1,200|mi|km}} tunnel, carrying Maglev trains, is planned to connect India’s biggest city Mumbai and emirate Fujairah (United Arab Emirates) through the Arabian Sea in a high-speed railway line to transport passengers, tourists and workers in just 2 hours. It had the support of Abdullah Alshehhi, chief consultant of Abu Dhabi National Advisory Office (a Masdar City-based consultancy), and the Gulf Cooperation Council.{{cite news | url=https://www.arabianbusiness.com/industries/technology/413680-tunnel-vision-could-underwater-project-connect-the-uae-india | title=Tunnel vision: Could underwater project connect the UAE and India? - Arabian Business: Latest News on the Middle East, Real Estate, Finance, and More | newspaper=Arabian Business | date=28 February 2019 }}{{cite web | url=https://www.constructionworld.in/transport-infrastructure/metro-rail-and-railways-infrastructure/uae-explores-futuristic-underwater-tunnel-to-india/25741 | title=UAE explores futuristic underwater tunnel to India }}{{Cite web |date=2023-05-09 |title=Major rail project in Middle East, US leverage against China-Russia |url=https://www.railfreight.com/specials/2023/05/09/major-rail-project-in-middle-east-us-leverage-against-china-russia/ |access-date=2023-05-17 |website=RailFreight.com |language=en-US}} It is considered the longest submarine tunnel project in the world and will have a depth of 15,000 feet below the surface of the Indian Ocean.{{Cite web |last=Bottini |first=Arianna |date=2022-07-11 |title=The LONGEST SUBMARINE TUNNEL project in the world: it will connect the Arab Emirates and India |url=https://www.reshumana.com/projects/the-longest-submarine-tunnel-project-in-the-world-it-will-connect-the-arab-emirates-and-india/ |access-date=2023-05-17 |website=Res Humana |language=en-US}}{{Cite web |last=Webster |first=Nick |date=2018-12-07 |title=Could India connect with the UAE via an undersea tunnel? |url=https://www.thenationalnews.com/uae/could-india-connect-with-the-uae-via-an-undersea-tunnel-1.800240 |access-date=2023-05-17 |website=The National |language=en}}

Also, Karachi (Pakistan) and Muscat (Oman) are also included future plans of train stations, making provision for a road to be constructed within the tunnel for cars and trucks as well as a floating hotel, shopping centres and fuel stations, featuring pipelines for oil and water. Expansion of the project might include the One Belt One Road Initiative, linking China to Pakistan economic corridor at Gwadar Port with UAE, through the Fujairah port to complement the Chinese silk road.{{Cite web |date=2019-02-20 |title=Watch: NABL presents Fujairah-Mumbai underwater train tunnel |url=https://safety4sea.com/watch-nabl-presents-fujairah-mumbai-underwater-train-tunnel/ |access-date=2023-05-17 |website=SAFETY4SEA |language=en-US}}

One of the longest tunnels in the world and - depending on definitions (total length versus length actually under water) - either the longest or the second longest underwater tunnel ahead or behind of the Channel Tunnel, the Seikan Tunnel links Japan's northernmost main island Hokkaido to Honshu. Initially only built to Cape gauge, the rail line running through the tunnel has since been converted to dual gauge to allow standard gauge services, particularly Shinkansen. The Tōya Maru accident of 1954, in which a train ferry sank in a typhoon, killing over a thousand people, was a major factor in tilting the decision towards construction of the tunnel. The tunnel opened in 1988 and Hokkaido Shinkansen started running through it in 2016.

The Philippines is planning to build a bridge that will span Manila Bay and connect the provinces of Bataan and Cavite. The Bataan–Cavite Interlink Bridge, once completed, will be {{convert|32.15|km|mi|sp=us}} long and will consist of two cable-stayed bridges, with a span of {{convert|400|and|900|m|ft|sp=us}} each. The National Economic and Development Authority (NEDA) approved the bridge project in early 2020 with a budget of {{Philippine peso|175.7 billion}}. The implementation of the bridge project is projected to last six years.{{cite news |last1=Flora |first1=Ian Ocampo |title=P175-B mega bridge project to connect CL, Southern Tagalog |url=https://www.sunstar.com.ph/article/1843223/Pampanga/Local-News/P175-B-mega-bridge-project-to-connect-CL-Southern-Tagalog |accessdate=June 25, 2020 |work=Sun Star Pampanga |date=February 6, 2020}}

In October 2020, the Department of Public Works and Highways (DPWH) signed a $59 million engineering design contract, awarded to the joint venture of T. Y. Lin International from the US and Korea's Pyunghwa Engineering Consultants Ltd., who are working in tandem with Geneva-based Renardet S.A. and local firm DCCD Engineering Corporation.{{cite news |url=https://www.adb.org/news/engineering-design-contract-awarded-adb-supported-bataan-cavite-bridge-project-philippines|title= Engineering Design Contract Awarded for ADB-Supported Bataan–Cavite Bridge Project in the Philippines|date=October 22, 2020 |work=Asian Development Bank |access-date=November 29, 2020}}

As of March 2023, the project's detailed engineering design is already 70% complete, according to DPWH. The construction of the bridge is targeted to start in late 2023.{{Cite news |date=2023-03-14 |title=DPWH: Construction of Bataan-Cavite Interlink Bridge to start in late 2023 |url=https://newsinfo.inquirer.net/1742509/dpwh-construction-of-bataan-cavite-interlink-bridge-to-start-in-late-2023 |access-date=2023-03-14 |newspaper=Philippine Daily Inquirer |language=en-US}}

{{Main|Bering Strait crossing}}

There is a proposal to span the Bering Sea with a bridge or tunnel called the Intercontinental Peace Bridge, the TKM-World Link or the AmerAsian Peace Tunnel. This would link the American Cape Prince of Wales with the Russian Cape Dezhnev. The link would consist of three tunnels connecting Alaska and Russia via two islands: Little Diomede (USA) and Big Diomede (Russia). The longest single tunnel would be {{convert|24|mi|km}}. Since the Bering Sea at the site of the proposed crossing has a maximum known depth of {{convert|170|ft|m}}, the tunnels might be dug with conventional tunnel boring machines of the type used to build the Channel Tunnel. The three tunnel proposal is considered{{who|date=May 2023}} to be preferable over a bridge due to severe environmental conditions, especially the inescapable winter ice damage.

Each proposed tunnel would be shorter than some current tunnels. The Channel Tunnel linking England with mainland Europe is about {{convert|31.34|mi|km}} long; the Seikan Tunnel, an ocean tunnel linking Hokkaido with Honshu in Japan is {{convert|33.46|mi|km}} long; and the Swiss Gotthard Base Tunnel through the Alps, opened in 2016, is {{convert|35.7|mi|km}} long.

For a bridge or tunnel to be useful, a road or railway must be built to connect it, despite the very difficult climate and very sparse local population. In Alaska, a {{convert|700|mi|km|adj=on}} link would be needed, and in Russia, a link more than {{convert|1,200|mi|km}} long must be constructed. Until around 2010, such road connections were suggested by enthusiasts only, but at that time both the Russian government and the Alaskan state government started to consider such roads. The Alaska Railroad is currently the only railroad in Alaska, and is not connected to the wider North American rail network, but plans for an A2A Railway linking it to Alberta, Canada and from there to the rest of the North American rail network are under consideration.

There are no viable options for a fixed link between Asia and Oceania. Excluding the Indonesia–Papua New Guinea border that divides the island of New Guinea, the shortest distances between Southeast Asia and Oceania still cover a significant distance across the sea between Indonesia and Australia. The closest would be Badu Island in Queensland's Torres Strait Islands, which is {{convert|123|km|mi}} away from Merauke Regency's coastal border with Papua New Guinea. Otherwise, in the Arafura Sea, Rimbija Island in the Northern Territory's uninhabited Wessel Islands is {{convert|300|km|mi}} south of Yos Sudarso Island, also in Merauke Regency; and across the Timor Sea, the northern tip of Melville Island is still {{convert|317|km|mi}} south of Selaru in the Tanimbar Islands of Maluku.Google Maps 2024

A tunnel/bridge between the Australian mainland and the island of New Guinea, bridging the Torres Strait, is not considered economically feasible owing to the great distance. Cape York in northern Queensland is 140 km away from New Guinea. This is a very long distance compared to existing tunnels or bridges, and the demand for car travel is not so high; as of 2009[http://forum.virtualtourist.com/discussion-475279-1-1-Travel-0-0-Papua_New_Guinea-discussion.html Australia PNG Indonesia by ship/ ferry] there are no car ferries between Australia and Papua New Guinea. Passenger travel is by air or private boat only.

The Cook Strait between North Island and South Island of New Zealand has been suggested for a fixed link. The length would be at least 22 km, and the water depth is around 200 meters.[https://charts.linz.govt.nz/charts/enc Electronic Navigation Charts (ENC) - list view] This is mostly considered a too complicated and costly project to be realised.

Ferry services link Vancouver Island to British Columbia on the Canadian Mainland and to the State of Washington in the US.

Proposals have been made for a fixed link to Vancouver Island for over a century. Because of the extreme depth and soft seabed of the Georgia Strait, and the potential for seismic activity, a bridge or tunnel would face monumental engineering, safety, and environmental challenges at a prohibitive cost.{{cite web |url=http://www.th.gov.bc.ca/publications/reports_and_studies/fixed_link/fixed_link.htm |title=A Potential Fixed Link to Vancouver Island - Ministry of Transportation |publisher=Th.gov.bc.ca |access-date=2010-09-13 |url-status=dead |archive-url=https://web.archive.org/web/20100821203226/http://www.th.gov.bc.ca/Publications/reports_and_studies/fixed_link/fixed_link.htm |archive-date=2010-08-21 }}

Prince Edward Island is linked to New Brunswick on the Canadian mainland by the Confederation Bridge which opened in 1997.

Various proposals have been considered for a fixed link consisting of bridges, tunnels, and/or causeways across the Strait of Belle Isle, connecting the Province of Newfoundland and Labrador's mainland Labrador region with the island of Newfoundland. This strait has a minimum width of {{convert|17.4|km|mi|abbr=on}}.

Nine bridges and 13 tunnels (including railroad tunnels) connect the New York City boroughs of Brooklyn and Queens, on Long Island, to Manhattan and Staten Island and, via these, to Newark in New Jersey and The Bronx on the mainland of New York state. However, no fixed crossing of the Long Island Sound exists east of New York City; most traffic from the mainland United States must pass through the city to access Long Island. Passenger and auto ferries connect Suffolk County on Long Island northward across the Sound to the mainland of New York state and eastward{{clarify|date=May 2020}} to the state of Connecticut. There have been various proposals, none successful, to replace these ferries with a fixed link across Long Island Sound to provide an alternate route around New York City for Long Island-bound traffic.

The Chesapeake Bay Bridge–Tunnel (CBBT) is a {{convert|23|mi|km|adj=mid|-long}} fixed link crossing the mouth of the United States' Chesapeake Bay, connecting the Delmarva Peninsula with Virginia Beach, Virginia. It opened in 1964.

The Overseas Highway is a {{convert|113|mi|km|adj=on}} highway carrying U.S. Route 1 (US 1) through the Florida Keys to Key West.

Ferry services between the US and Cuba and between Cuba and Haiti were common before 1960, but were suspended due to the United States embargo against Cuba. After the normalization of U.S.-Cuba diplomatic relations by U.S. President Barack Obama and Cuban President Raúl Castro, some American companies began plans to provide regular ferry services between Florida and Cuba. However, President Donald Trump reinstated many travel restrictions towards Cuba during his term, including prohibition of direct ferry services.{{Cite web|title=Taking a Ferry From Florida to Cuba: No Longer an Option in 2020|url=https://www.tripsavvy.com/take-a-ferry-to-cuba-4077864|archive-url=https://web.archive.org/web/20200922120946/https://www.tripsavvy.com/take-a-ferry-to-cuba-4077864|url-status=dead|archive-date=September 22, 2020|access-date=2020-11-11|website=TripSavvy|language=en}}

There is only one regular ferry to Havana from a foreign port: Cancún, Mexico.{{Cite web|url=http://www.travelcubacaribbean.com/cruise/cruise.asp|title = Cruise to Cuba from Cancun - TravelCubaCaribbean - Your travel agency to Cuba!}}

A ferry travels between Mayagüez in Puerto Rico and Santo Domingo in the Dominican Republic.{{Cite web |url=http://www.ferriesdelcaribe.com/ingles/ |title=Ferries del Caribe Inc. D/B/A Cruceros del Caribe |access-date=2020-04-18 |archive-date=2009-01-26 |archive-url=https://web.archive.org/web/20090126063932/http://www.ferriesdelcaribe.com/ingles/ |url-status=dead }}

There have been proposals for a direct link between Key West (US) to Havana (Cuba) by tunnel or bridge{{Cite web |title=The Key West-Havana Tunnel |url=http://www.changingthetimes.net/samples/preww1/key_west_tunnel.htm |access-date=2023-05-20 |website=www.changingthetimes.net}}{{Cite web |date=2007-08-16 |title=What does the bridge to Cuba mean for the North? |url=https://www.northernontariobusiness.com/columns/robinson/what-does-the-bridge-to-cuba-mean-for-the-north-364578 |access-date=2023-05-21 |website=Northern Ontario Business |language=en}} and also for a direct tunnel between Florida and The Bahamas.{{Cite web |last=By |date=1990-12-02 |title=TAKE THE TUNNEL TO THE BAHAMAS |url=https://www.orlandosentinel.com/news/os-xpm-1990-12-02-9011291012-story.html |access-date=2023-05-21 |website=Orlando Sentinel |language=en-US}}

On 2009, there was a proposal to build a bridge between Ceiba (on Puerto Rico island) and Vieques island, having an estimated cost of $600 million. The main goal was to cut travel time to and from the small island town that is currently served by daily ferry runs.{{Cite web |date=2009-07-21 |title=Apoyo a construcción de puente a Vieques - El Nuevo Día |url=https://www.elnuevodia.com/apoyoaconstrucciondepuenteavieques-593321.html |access-date=2024-03-30 |archive-url=https://web.archive.org/web/20090721001216/https://www.elnuevodia.com/apoyoaconstrucciondepuenteavieques-593321.html |archive-date=2009-07-21 }}

After the independence of Trinidad and Tobago, members in the government have spoken of constructing a physical link between the islands of Trinidad and Tobago, wanting to physically unify the country.{{cite hansard|jurisdiction=Trinidad and Tobago|house=House of Representatives|date=October 6, 2003|url=http://www.ttparliament.org/hansards/hh20031006.pdf#page=35|speaker=Hon. P. Manning|position=The Prime Minister and Minister of Finance|page_start=41|page_end=41|title=Appropriation Bill (Budget)}} {{Webarchive|url=https://web.archive.org/web/20160305131654/http://www.ttparliament.org/hansards/hh20031006.pdf#page=35 |date=March 5, 2016 }} As public discussion and commentary ensued over feasibility and cost,{{cite news |last=Kangal |first=Stephen |date=December 17, 2006 |title=Letter to the EMA – Re: The Rapid Rail System |newspaper=Trinidad and Tobago News Blog |publisher=Trinidad and Tobago News |url=http://www.trinidadandtobagonews.com/blog/?p=140 |access-date=July 13, 2013 |quote=In addition, this should not be limited to folks in Central, but eventually spread toward the East, South, and even Western areas. I would like to see the implementation of toll boots along our highways, as this can help discourage congestions as drivers would see it more in their interest to park and ride, like the big boys and gals do in the more industrialized world. While we are at it, perhaps it’s time to begin a follow up on long delayed talks to build a bridge between Toco and Tobago, This would certainly serve as a first step to truly linking the two islands ,as opposed to the almost diabolical, and economically imbalanced charade that existed for too long under our past five post colonial Prime Ministers.}} an alternative proposal of a Gulf of Paria crossing was made of constructing a shorter connection which would connect Trinidad and Venezuela.{{cite news |last=Ramoutar |first=Paras |date=September 17, 2011 |title=Build Toco-Tobago bridge with China's assistance |newspaper=Trinidad and Tobago Newsday |publisher=Daily News Ltd. |url=http://www.newsday.co.tt/letters/0,147411.html |access-date=July 9, 2013}}

In 2017, China showed interest in the construction of a mega bridge in the Caribbean Sea to connect Tobago and Trinidad.{{Cite web |last=Neaves |first=Julien |date=2018-09-11 |title=Rowley: Tobago bridge not feasible - Trinidad and Tobago Newsday |url=https://newsday.co.tt/2018/09/11/rowley-tobago-bridge-not-feasible/,%20https://newsday.co.tt/2018/09/11/rowley-tobago-bridge-not-feasible/ |access-date=2023-05-20 |website=newsday.co.tt |language=en-US}}{{Cite web |date=2017-10-17 |title=China unveils US$15Bn mega bridge {{!}} The Trinidad Guardian Newspaper |url=http://guardian.co.tt/news/2017-10-16/china-unveils-us15bn-mega-bridge |access-date=2023-05-20 |archive-url=https://web.archive.org/web/20171017102632/http://guardian.co.tt/news/2017-10-16/china-unveils-us15bn-mega-bridge |archive-date=2017-10-17 }}

On modern times, there have been studies from the Department of Civil & Environmental Engineering, from University of the West Indies at St. Augustine, that have developed studies for a possible bridge linking between Venezuela and Tobago, but only as case study, without official support.{{Cite web |title=(PDF) A Bridge Linking Trinidad and Venezuela: A Case Studyapett.org/journal/vol43n2_Oct2015/P05_15005_v43n2p32-43(AAli)-Oct2015.pdf · A Bridge Linking Trinidad and Venezuela: A Case Study |url=https://dokumen.tips/documents/a-bridge-linking-trinidad-and-venezuela-a-case-aali-oct2015pdf-a-bridge-linking.html |access-date=2023-05-20 |website=dokumen.tips |language=el}}

In Venezuela, the General Rafael Urdaneta Bridge connects Maracaibo with much of the rest of the country, being a bridge that crosses the narrowest part of Lake Maracaibo, in Zulia (northwestern Venezuela). There is another plan of a Second bridge over Lake Maracaibo for the construction of a mixed road-rail bridge that would link the Zulia cities of Santa Cruz de Mara and Punta de Palmas, located on both sides of Lake Maracaibo, in the Miranda Municipality.{{Cite web |title=Nigale invisible: casi 10 años tiene la construcción del segundo puente sobre el lago |url=https://es.linkedin.com/pulse/nigale-invisible-casi-10-a%C3%B1os-tiene-la-construcci%C3%B3n-del-garc%C3%ADa |access-date=2023-05-20 |website=es.linkedin.com |language=es}}

File:Darien_Gap_OSM.svg between Yaviza, Panama and Turbo, Colombia |left]]

{{Main|Darién Gap}}

A notable break in the Pan-American Highway is a section of land located in the Darién Province in Panama and the Colombian border called the Darién Gap. It is an {{convert|87|km|mi|adj=on}} stretch of rainforest. The gap has been crossed by adventurers on bicycle, motorcycle, all-terrain vehicle, and foot, dealing with jungle, swamp, insects, kidnapping, and other hazards.

Some people, groups, indigenous populations, and governments are opposed to completing the Darién portion of the highway. Reasons for opposition include protecting the rain forest, containing the spread of tropical diseases, protecting the livelihood of indigenous peoples in the area, and reducing the spread of drug trafficking and its associated violence from Colombia.

The Hercilio Luz Bridge is the first bridge constructed to link the Island of Santa Catarina to the mainland Brazil. Two additional crossings connecting the island to the mainland exist: Colombo Salles Bridge and Pedro Ivo Campos Bridge.

File:Mapa Puente Bicentenario.png map.]]It's a construction project for a bridge that will cross the Chacao Channel. It is intended to unite the Isla Grande de Chiloé with the Chilean continental territory, in the Los Lagos Region. The opening of the bridge is planned for 2025.{{cite web |date=2017-09-13 |title=RM Bridge Streamlines Design and Analysis of South America's Longest Suspension Bridge |url=https://csengineermag.com/rm-bridge-streamlines-design-analysis-south-americas-longest-suspension-bridge/ |accessdate=21 March 2018 |website=Civil + Structural Engineer}}{{cite web |title=Chacao Bridge - Chile |url=https://www.aaj.no/prosjekter/chacao/?pdf=3288 |accessdate=21 March 2018 |website=Aas-Jakobsen |language=Norwegian}}{{Cite web |date=5 November 2019 |title=Se alarga el plazo para el Puente Chacao: Hyundai pide segunda extensión para concluir obras y apunta a 2025 |url=https://www.latercera.com/la-tercera-pm/noticia/se-alarga-plazo-puente-chacao-hyundai-pide-segunda-extension-concluir-obras-apunta-2025/888976/}} It will be the longest suspension bridge in Latin America.{{Cite web |title=Página 2 {{!}} El Llanquihue - 18.02.2016 |url=https://www.ellanquihue.cl/impresa/2016/02/18/full/cuerpo-principal/2/ |access-date=2023-05-18 |website=www.ellanquihue.cl/ |language=es}} Previously there were suggestion of a connection by tunnel, but were rejected due to financial problems.{{Cite web |title=Proponen construir túnel para conectar la isla de Chiloé al continente |url=http://www.mundomaritimo.cl/noticias/proponen-construir-tunel-para-conectar-la-isla-de-chiloe-al-continente |access-date=2023-05-18 |website=www.mundomaritimo.cl}}

At the end of the 19th century, Argentine President Domingo Sarmiento presented the "Argirópolis" project; which included building railway bridges uniting both countries through the Martín García island.

Several land connection projects through the Río de la Plata were evaluated by the governments of Argentina and Uruguay (also Mercosur), with the objective of erecting a road for vehicular, rail or both types of transit. Although most of the proposals involve the construction of bridges, others also mention sub-fluvial tunnels as a possible alternative. The project would consist to link Colonia del Sacramento in Uruguay to Punta Lara in Argentina.{{Cite web |date=2012-09-08 |title=Los expedientes de los proyectos que nunca se hicieron realidad {{!}} Diario La Prensa |url=http://www.laprensa.com.ar/395635-Los-expedientes-de-los-proyectos-que-nunca-se-hicieron-realidad.note.aspx |access-date=2023-05-18 |archive-url=https://web.archive.org/web/20120908015909/http://www.laprensa.com.ar/395635-Los-expedientes-de-los-proyectos-que-nunca-se-hicieron-realidad.note.aspx |archive-date=2012-09-08 }}{{Cite web |last=Redacción |title="Cinco puentes Colonia-Buenos Aires" |url=https://www.elobservador.com.uy/nota/-cinco-puentes-colonia-buenos-aires--2021111502 |access-date=2023-05-18 |website=El Observador}}{{Cite web |date=2018-06-03 |title=La reaparición de un puente soñado |url=https://www.elpais.com.uy/informacion/sociedad/la-reaparicion-de-un-puente-sonado |access-date=2023-05-18 |website=EL PAIS |language=en}}{{Cite web |title=Confirmado: se reflota proyecto de puente Colonia - Buenos Aires |url=https://www.ambito.com/politica/confirmado-se-reflota-proyecto-puente-colonia-buenos-aires-n3959882 |access-date=2023-05-18 |website=www.ambito.com}}

{{Main|Transatlantic tunnel}}

A transatlantic tunnel is a theoretical tunnel that would span the Atlantic Ocean between North America and Europe, perhaps enabling mass transit. Some proposals envision technologically advanced trains reaching speeds of {{convert|500|to|8000|km/h|-2}}.{{cite episode|title=Transatlantic Tunnel |url=http://dsc.discovery.com/convergence/engineering/transatlantictunnel/interactive/interactive.html |series=Extreme Engineering |series-link=Extreme Engineering |credits=Joseph Giotta (Narrator), Powderhouse Productions |network=Discovery Channel |airdate=16 April 2003 |url-status=dead |archive-url=https://web.archive.org/web/20110927014656/http://dsc.discovery.com/convergence/engineering/transatlantictunnel/interactive/interactive.html |archive-date=27 September 2011 }} Most conceptions of the tunnel envision it between the United States and the United Kingdom ‒ or more specifically between New York City and London.

Advantages compared to air travel would be increased speed and use of electricity instead of oil-based fuel.

The main barriers to constructing such a tunnel are cost, with estimates of between $88 billion and $175 billion, as well as the limits of current materials science.{{cite journal|title=Trans-Atlantic MagLev: Vacuum Tube Train|author=Carl Hoffman|journal=Popular Science|date=12 April 2004|url=http://www.popsci.com/scitech/article/2004-04/trans-atlantic-maglev|access-date=27 September 2011}}

The proposed routes are a direct link from the US to Europe, or from the US, crossing Canada, Greenland, Iceland and the Faroe Islands, to the United Kingdom, using an underwater vacuum tube train.{{Cite web |last=Hoffman |first=Carl |date=2004-04-12 |title=Trans-Atlantic MagLev |url=https://www.popsci.com/scitech/article/2004-04/trans-atlantic-maglev/ |access-date=2023-05-17 |website=Popular Science |language=en-US}}{{Cite web |title=Transatlantic Maglev |url=https://www.maglev.net/transatlantic-maglev |access-date=2023-05-17 |website=www.maglev.net}}

The Maritime Research Institute Netherlands (Marin), in 2019, tested a model trans-Atlantic underwater tunnel between the United States and Europe capable of supporting hyperloop.{{Cite web |title=MARIN Tests Underwater Hyperloop Tunnel |url=https://maritime-executive.com/index.php/article/marin-tests-underwater-hyperloop-tunnel |access-date=2023-05-17 |website=The Maritime Executive |language=en}}{{Cite web |date=2019-10-16 |title=Watch: Researchers test transatlantic underwater hyperloop tunnel |url=https://safety4sea.com/watch-researchers-test-transatlantic-underwater-hyperloop-tunnel/ |access-date=2023-05-17 |website=SAFETY4SEA |language=en-US}}{{Cite web |title=Transatlantic Hyperloop Tested by Dutch Marine Research Institute |url=https://www.hydro-international.com/content/news/hyperloop-tested-by-marin |access-date=2023-05-17 |website=www.hydro-international.com |language=en}}

• Atlantropa
• Orkney tunnel
• Trans-Asian Railway
• List of transport megaprojects
• List of straits

{{reflist}}

{{refbegin}}

• "The Three Americas Railway: An International and Intercontinental Enterprise" book written in 1881 by Hinton Rowan Helper discusses the need for an Intercontinental Highway, using railroads, starting on page 418.
• "The Rotarian", January 1936. Article "Seeking Peace in a Concrete Way" starting on page 42.
• "Looking far north: the Harriman Expedition to Alaska, 1899" written in 1982 by William H. Goetzmann, Kay Sloan, writes that Harriman in 1899 proposed a "Round the World Railroad" (page 128). The authors go on to write that Harriman traveled to Japan a few years later to continue this proposal.
• "The Bering Strait Crossing: A 21st Century Frontier Between East and West" by James Oliver published in 2006 (256 pages) mentions extensively the Intercontinental Highway. He goes on to mention that the notion of a global highway has been around for hundreds of years including William Gilpen, who suggests it in 1846 was a proponent of a global rail highway to link to the then being proposed European and Asiatic Railway.
• "Planning and Design of Bridges" by M. S. Troitsky, 1994 describes many of the bridges and tunnels proposed in the Trans Global Highway article including on page 39 this book mentions that in 1958, T.Y. Lin mentions the possible construction of a Bering Strait bridge (and obviously a needed highway network).
• Alaska History: A Publication of the Alaska Historical Society, Volumes 4-6 (1989) mentions on page 6 that in 1892, a man named Strauss proposed a global highway and a man made bridge over the Bering Strait. The article goes on to mention the Lin proposal of 1958.
• "Maritime Information Review" a publication of the Netherlands Maritime Information Centre, in 1991 had an extensive article, on "strait crossings" covering the then proposed Bering Strait bridge, the Gibraltar Tunnel and so on, and mentions the proposed global highway network.
• Popular Mechanics Apr 1994 has an article "Alaska Siberia Bridge" and the article goes on to mention the construction of a global highway.

{{refend}}

• [http://www.schillerinstitute.org/economy/maps/maps3.html#bering%20straits The Schiller Institute article on the Trans Global Highway] {{Webarchive|url=https://web.archive.org/web/20140419044419/http://www.schillerinstitute.org/economy/maps/maps3.html#bering%20straits |date=2014-04-19 }}
• [http://wikivoyage.org/ Wikivoyage], Wikimedia's global travel guide with information on driving in each country

Category:Exploratory engineering

Category:Transportation planning

Category:Proposed undersea tunnels

Category:Proposed bridges

Category:Transcontinental crossings