Lists of mountains in Ireland#Marilyns

{{Main article|Lists of mountains and hills in the British Isles}}

File:Doolough - MweelRea.JPG from Doo Lough in Connemara. Mweelrea is the provincial top of Connacht, the county top of Mayo, the 5th highest Irish P600 mountain, the 14th highest Irish Marilyn mountain, the 16th highest Irish MountainViews mountain, the 26th highest Irish Arderin/Hewitt mountain, and the 34th highest Irish Vandeleur-Lynam/Nuttall mountain. It is not a Furth (or Irish Munro), and therefore not a Real Munro.]]

There is no consensus on the definition of "mountain", but in Britain and Ireland it is often taken to be a summit over 2,000 ft, or more latterly, 600 m.{{cite book | last=Nuttall | first=John & Anne | title=The Mountains of England & Wales – Volume 2: England| edition=3rd| year=2008| publisher=Cicerone| location=Milnthorpe, Cumbria | isbn=978-1-85284-037-2}}{{Cite web|title=A Mountain is a Mountain - isn't it?|url=https://www.go4awalk.com/uk-mountains-and-hills/a-mountain-is-a-mountain.php|access-date=2023-01-02|website=www.go4awalk.com}}{{Cite web |title=mountain |url=https://www.dictionary.com/browse/mountain|access-date=2023-01-02|publisher=dictionary.com}}Wilson, Peter (2001). Listing the Irish hills and mountains in Irish Geography, Vol 34(1), University of Ulster, Coleraine, p. 89. [http://www.ucd.ie/gsi/pdf/34-1/hills.pdf] (pdf) There is less consensus about the topographical prominence requirement (e.g. the change in elevation required between neighbouring mountains), which can vary between {{convert|30-150|m|abbr=on}}. Prominence is even strongly debated regarding UIAA classification of Himalayan mountains.{{cite web|url=https://www.bbc.com/news/science-environment-24571309|title=Nepal mountain peak expansion bid stalls|publisher=BBC News|date=18 October 2013}}{{cite web|url=http://www.markhorrell.com/blog/2014/a-funny-name-for-a-mountain/|title=A funny name for a mountain|publisher=Mark Horrell|date=4 June 2014|quote=I explained how these five ridge tops couldn’t possibly be classified as 8000m peaks in their own right because each of them requires less than 135 metres of re-ascent between their respective parent peaks, Kangchenjunga and Lhotse (known as topographic prominence). It seems that where logic and common sense fail the NMA feels that flattery may work instead. }} In the alps, the UIAA requires a prominence of over 30 m to be a "peak" and over 300 m to be a "mountain".{{cite web|url=https://www.theuiaa.org/mountaineering/mountain-classification/|title=MOUNTAIN CLASSIFICATION|publisher=UIAA|date=March 1994|quote=Topographic criterium: for each summit, the level difference between it and the highest adjacent pass or notch should be at least 30 m (calculated as average of the summits at the limit of acceptability).}}

The lowest threshold of prominence in Britain and Ireland is {{convert|15|m|0}}. The only definition in which prominence is not used, is where topographic isolation is used (e.g. the use of "sufficient separation" for Munros). Most Britain and Ireland definitions no longer categorise prominences below {{convert|30|m|0}} (e.g. no new Nuttalls and Vandeleur-Lynams), and peaks with a prominence between {{convert|30-150|m|0}} are now defined as tops rather than mountains (e.g. the 227 Munro Tops).

In Ireland, a prominence threshold of {{convert|100|m|0}} is proposed for a mountain.

{{ordered list|type=lower-roman

|Furth. A Munro outside of Scotland with height over {{convert|3000|ft|0}};{{efn|While there is no explicit prominence requirement, the Scottish Mountaineering Club ("SMC") reviews aspects like prominence, and isolation, when deciding on the official list of Munros. All of the SMC list of 34 Furths have a prominence over {{convert|30|m|0|abbr=on}}, except for Caher West Top, which is {{convert|24|m|0|abbr=on}}.}}[http://www.smc.org.uk/Hillwalking/HillKeyFacts.php Mountains – Key Facts. The Munros, Corbetts, Grahams, Donalds & Furths] {{webarchive|url=https://web.archive.org/web/20120822093115/http://www.smc.org.uk/Hillwalking/HillKeyFacts.php |date=2012-08-22 }} at www.smc.org.uk. Accessed on 9 Feb 2013. Ireland has 13 Furths, or "Irish Munros";

|Real Munro. A Munro, or Furth, with prominence over {{convert|150|m|0|abbr=on}};{{cite web|url=https://www.telegraph.co.uk/travel/galleries/most-beautiful-impressive-best-munros-to-climb/ |archive-url=https://ghostarchive.org/archive/20220112/https://www.telegraph.co.uk/travel/galleries/most-beautiful-impressive-best-munros-to-climb/ |archive-date=2022-01-12 |url-access=subscription |url-status=live|title=Magnificent munros: 17 Scottish mountains to bag in your lifetime|publisher=The Telegraph|date=13 April 2017|quote=Of the 282, 200 are said to have a summit prominence of over 150 metres and are therefore known as "real monros", but that's for another day.}}{{cbignore}}{{cite web| url=http://www.peakbagger.com/list.aspx?lid=-926010| title=Real Munros| publisher=Peakbaggers| access-date=9 January 2018}} Ireland has 5 Real Munros;

|P600 (the "Majors"). British Isles peak of any height, with prominence over {{convert|600|m|0|abbr=on}}; Ireland has 26 P600s;{{efn|P600 an international classification of major peaks (along with the P1500, or Ultra-prominent peak), which was first applied by Alan Dawson (who called them "Majors"), and has become popular in the British Islands.{{cite web|url=http://www.hill-bagging.co.uk/P600m.php|title=The P600 peaks|publisher=HillBagging.co.uk}}}}{{cite web|url=http://www.peaklist.org/WWlists/GB/GB600m.html|title=THE BRITISH ISLES COMBINED LIST FOR THE UNITED KINGDOM AND REPUBLIC OF IRELAND|author1=Alan Dawson|author2=Rob Woodall|author3=Jonathan de Ferranti|date=2006|quote= Previously available lists used a cutoff of 2,000 feet (609.6 meters). The 2000 foot cutoff would result in a total of 111 mountains: 90 for Great Britain, 1 for the Isle of Man, and 20 for Ireland. By lowering the cutoff to 600 meters (in order to be consistent with upcoming lists for Europe), we now reach a total of 119 mountains, including 93 for Great Britain, 1 on Man, and 25 in Ireland.}}

|Marilyn. British Isles peak of any height, with a prominence of over {{convert|150|m|0|abbr=on}}; Ireland has 454 Marilyns;

|Hewitt. England, Wales or Ireland peak over {{convert|2000|ft|0|abbr=on}}, with prominence of over {{convert|30|m|0|abbr=on}}; Ireland has 209 Hewitts;

|Vandeleur-Lynam.{{efn|The definition of an Irish Vandeleur-Lynam is similar to a "Nuttall" in England and Wales, except that the Vandeleur-Lynam is fully metric.}} Irish peak over {{convert|600|m|0|abbr=on}}, with prominence over {{convert|15|m|0|abbr=on}}; Ireland has 274{{cite web|url=https://mountainviews.ie/lists/vandeleur-lynam/?PHPSESSID=6lpes93lcdlq890dprmqqu4dn6|title=Vandeleur-Lynams: Irish mountains of 600+m with a prominence of 15m|publisher=MountainViews.ie|date=October 2018}} Vandeleur-Lynams;{{efn|name="vl"|A Vandeleur-Lynam is a hill in Ireland at least 600 metres high with a drop of at least 15 metres on all sides. In 1952 Joss Lynam produced a list of 2000ft summits with 50ft drop with assistance from Rev CRP Vandeleur. Joss Lynam updated a version of this list and published it in a reprint of "Mountaineering in Ireland" by Claude Wall printed in 1976. The metricised equivalent was published in 1997. Lynam was actively involved with the list until 2002, thereafter assisting MountainViews with subsequent revisions until his death in 2011.{{cite web|url=https://www.hill-bagging.co.uk/VandeleurLynams.php?ct=I|title=The Vandeleur-Lynams|publisher=HillBagging.co.uk}}}}

|Arderin.{{efn|name="ard"|The Arderin an Irish–equivalent of a "Hewitt", having the same metric prominence requirement of {{convert|30|m|0|abbr=on}}, but the Arderin height requirement is lower, and metric, at {{convert|500|m|0|abbr=on}}.}} Irish peak over {{convert|500|m|0|abbr=on}}, with a prominence of over {{convert|30|m|0|abbr=on}}; Ireland has 409{{cite web|url=https://mountainviews.ie/lists/arderin/|title=Arderins: Irish mountains of 500+m with a prominence of 30m|publisher=MountainViews.ie|date=October 2018}} Arderins;{{efn|An Arderin is a hill in Ireland of 500m or over with a drop of at least 30m on all sides. This list was drawn up in 2002 by the MountainViews publisher [Simon Stewart] from an early listing of the Myrddyn Deweys with those hills from the Vandeleur-Lynams which meet the higher drop criterion. The actual list name, created in 2009, comes from the 527 m hill, Arderin, which is the County Top for both Laois and Offaly and means, from the Irish, "Height of Ireland".{{cite web|url=https://www.hill-bagging.co.uk/Arderins.php|title=The Arderins|publisher=HillBagging.co.uk}}}}Mountainviews, (September 2013), "A Guide to Ireland's Mountain Summits: The Vandeleur-Lynams & the Arderins", Collins Books, Cork, {{ISBN|978-1-84889-164-7}}

|MountainViews.{{efn|MountainView's classification is a popular modern standard for categorising mountains in the UK.{{cite web|url=http://www.prominentpeaks.org.uk/peaks-classification.php|quote=The UK and Ireland are a family of islands, so the issue of plateau areas does not arise. The authors have concluded that good criteria for the UK are a minimum height of 500 metres and prominence of 100 metres. This is the basis for the UK Prominent Peaks database.|title=Principles of Peak Classification|publisher=ProminentPeaks.org.uk|author1=Jim Bloomer|author2=Roddy Urquhart|date=2018}}}}{{efn|name="mvs"|MountainViews was created in 2002 by Simon Stewart as a non–profit online database for climbers in Ireland to document and catalogue their Irish climbs.{{cite web|url=https://www.mountaineering.ie/hillwalking/mountainviews/|title=MountainViews.ie, a hillwalking resource for Ireland|publisher=Mountaineering Ireland (Irish Mountaineering Council)|date=2014}} Its main data feed is taken from the Ordnance Survey Ireland ("OSI"), however, it also integrates other established Irish mountain databases such as the Paul Tempan Loganim Irish Placenames Database.{{cite web|url=https://mountainviews.ie/credits/|title=MountainViews Sources and Credits|publisher=MountainViews.ie|author=Simon Stewart|date=2018}} Collins Press published its Online Datase in 2013 in the book: A Guide to Ireland's Mountain Summits: The Vandeleur-Lynams & the Arderins. MountainViews is also partnered with the important Database of British and Irish Hills ("DoBIH"), which is the main live database for the categorisation of mountains and hills in the British Isles.}} Irish peak over {{convert|500|m|0|abbr=on}}, with prominence over {{convert|100|m|0|abbr=on}}; Ireland has 221 such mountains.{{efn|MountainViews defines Irish peaks that meet this criterion as being "Irish mountains".}}

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File:Hill lists diagram Ireland.png).]]

{{anchor|Dillon}}The term Dillon is used to describe any of the 212 Irish summits in Paddy Dillon's well–regarded Irish 2010 climbing guidebook: "The Mountains of Ireland". All of Dillon's summits are over {{convert|2000|ft|abbr=on}}, and almost all have a prominence above {{convert|30|m|abbr=on}} (i.e. they are very similar to the list of 209 Irish Hewitts).{{cite web|url=http://www.hills-database.co.uk/database_notes.html#list_of_lists|title=Background to the lists|publisher=Database of British and Irish Hills|date=2 August 2018|quote=Dillons: Hills in Ireland at least 2,000 feet high published in The Mountains of Ireland. There is no prominence criterion. 15 Dillons are not Hewitts; 14 have drop <30m, while 20213 Corcog has a 609m spot height (the old 1:10560 map shows 2012ft which converts to 610.6m on the new datum). 12 Hewitts are not Dillons.}}

{{anchor|Myrddyn Deweys}}The term Myrddyn Deweys are peaks in Ireland, between 500 metres to {{convert|2,000|ft|1|abbr=off}} in height, with a prominence above {{convert|30|m|ft|abbr=off}}, which was published by Michael Dewey and Myrddyn Phillips in 2000. Myrddyn Deweys are the Irish equivalent of Deweys, which extend the Hewitt classification down to 500 metres. There are 200 Myrddyn Deweys.{{cite web|url=https://www.hill-bagging.co.uk/MyrddynDeweys.php?ct=I|title=Myrddyn Deweys|publisher=HillBaggingUK|quote=The Myrddyn Deweys are hills in Ireland with a height between 500-609m and prominence of 30m. The list was researched by Michael Dewey and Myrddyn Phillips and was made freely available to the Mountaineering Council of Ireland in 2000. In 2011 the data was re-examined against the latest mapping. [...] There are 200 Myrddyn Deweys.|access-date=7 November 2018|archive-date=8 November 2018|archive-url=https://web.archive.org/web/20181108025940/https://www.hill-bagging.co.uk/MyrddynDeweys.php?ct=I|url-status=dead}}

MountainViews was created in 2002 by Simon Stewart as a non–profit online database for climbers in Ireland to document and catalogue their Irish climbs.{{cite web|url=https://www.mountaineering.ie/hillwalking/mountainviews/|title=MountainViews.ie, a hillwalking resource for Ireland |publisher=Mountaineering Ireland (Irish Mountaineering Council)|date=2014}} Its main data source are from the Ordnance Survey Ireland (OSI) maps, although it also conducts its own surveys, which the OSI has integrated into its own database, and it also integrates other important Irish mountain databases such as the Paul Tempan's work with the Placenames Database of Ireland (Loganim). Collins Press published the MountainView Online Datase in 2013 in the book: A Guide to Ireland's Mountain Summits: The Vandeleur-Lynams & the Arderins.

Since 2012, MountainViews has been partnered with the Database of British and Irish Hills (DoBIH), which is the main live database for the categorisation of mountains and hills in Britain and Ireland.{{cite web |title=Welcome |url=http://www.hills-database.co.uk/index.html |website=The Database of British and Irish Hills |access-date=10 October 2018}}{{cite web|url=https://www.ordnancesurvey.co.uk/blog/2016/11/birthday-celebrations-two-new-nuttalls/|title=Birthday celebrations with two new Nuttalls|publisher=Ordnance Survey|date=23 November 2016|quote=DoBIH was founded by Graham Jackson and Chris Crocker as a personal tool to help them log their own hill ascents. However, over the years DoBIH evolved into something much bigger with six editors and many hillwalkers supplying data.}}{{cite web|url=https://www.rhb.org.uk/marhofn/marhofn316/marhofn31620.htm|title=The Database of British and Irish Hills - past, present and future|publisher=The Relative Hills of Britain (rhb.org.uk)|date=May 2016}} However, MountainViews can differ slightly from DoBIH on the measurements for certain Irish mountains.{{efn|name="mv"|{{As of | October 2018}}, the Irish MountainViews Online Database lists the prominence of Knockbrinnea (W) as 29m, and Carrignabinnia as 27 m, and thus they do not qualify as Irish Arderins, which means that MountainViews does not classify these two peaks as Hewitts or Simms; the total number of Irish Arderins over 2,000 ft is thus 207. The DoBIH however uses the Harvey Tables which list the prominence for both at 30 m, and thus the DoBIH class them as Irish Hewitts and Simms, giving 209 Irish Hewitts and 224 Irish Simms on the DoBIH tables.}}

{{see also|MacGillycuddy's Reeks#List of peaks}}

The MacGillycuddy's Reeks range contains Ireland's highest mountain, Carrauntoohil {{convert|1038.6|m|abbr=on}}, and the Reeks is the highest range of peaks in Ireland.{{cite book | last1 = Ryan | first1 = Jim | title = Carrauntoohil and MacGillycuddy's Reeks: A Walking Guide to Ireland's Highest Mountains | publisher = Collins Press | isbn = 978-1905172337 | year = 2006 }} However, many of its peaks do not meet all classification criteria for a "mountain" (e.g. particularly the {{convert|100-150|m|abbr=on}} in elevation change from neighbouring mountains), and many are not in the 100 Highest Irish Mountains. Regardless, the range contains ten of the thirteen Scottish Furths in Ireland, and given its importance, and as an important example of complexity of mountain classification, the ten highest Reeks are listed below:

(any height, prominence over 100 m)

This is the MountainViews{{efn|name="mvs"}} 100 Highest Irish Mountains list, which was published by Collins Press in the 2013 book: A Guide to Ireland's Mountain Summits: The Vandeleur-Lynams & the Arderins. It combines Paul Tempan's 2012 research into Irish mountains and Irish mountain names. The list requires a prominence of over {{convert|100|m|0|abbr=on}}, a compromise between the popular British Isles Marilyn criteria of 150 metres (see List of Marilyns in the British Isles for a ranking of Irish Marilyns by height and by prominence), and the Simms–Hewitt–Arderins criteria of 30 metres (see List of mountains of the British Isles by height for a ranking of Irish Simms by height and by prominence).{{cite web|url=https://mountainviews.ie/credits/|title=Credits and Acknowledgements: Lists of the summits, islands and coastal features for Ireland.|publisher=Mountainview.ie|date=2018|quote=The "Hundred Highest" list includes summits with a prominence at a minimum of 100 m, and has been introduced to give a height based list, not too long, with a spread of locations for Ireland.}} It is a widely used list,{{cite web|url=https://outsider.ie/ireland/highest-mountains-ireland/|title=10 of the Highest Mountains to Climb in Ireland|quote=We’ve compiled a list of the 10 highest mountains in Ireland for you to get your teeth into.|publisher=Outsider.ie|date=2018}}{{cite web|url=https://outsider.ie/ireland/irish-mountains/|title=The Complete Guide to Exploring Ireland's Mountains|publisher=Outsider.ie|date=2018|quote=Top 50 highest peaks in Ireland: MountainViews.ie}} and it contains 25 of the 26 Irish P600s (Slieve Snaght, a P600, did not make the 100 Highest).

{{legend|#cff|Real Munro: Height over {{convert|3000|ft|0}}, prominence over {{convert|150|m|0}}.}}

{{legend|#cfc|P600: Any height, prominence over {{convert|600|m|0}}.}}

{{see also|List of Hewitt mountains in England, Wales and Ireland}}

(height above 500 m, prominence over 30 m)

A noted definition of an Irish mountain over the lower height threshold of {{convert|500|m|0|abbr=on}}, is the Arderins list, but which meets the minimum requirement for a "mountain" with a prominence above {{convert|30|m|0|abbr=on}}, and is an Irish equivalent of the Hewitt (the 207 Arderins over {{convert|2000|ft|0|abbr=on}} are the 207–209 Irish Hewitts{{efn|name="mv"}}), or the Simm (the 222 Arderins over {{convert|600|m|0|abbr=on}} are the 222–224 Irish Simms{{efn|name="mv"}}). The 199 Arderins below {{convert|2000|ft|0|abbr=on}} are the Myrddyn Deweys (e.g. the total of the 207 Irish Hewitts and the 199 Myrddyn Deweys equal the 406 Irish Arderins).

MountainView's Online Database{{efn|name="mvs"}} of Arderins was published by Collins Press in the 2013 book: A Guide to Ireland's Mountain Summits: The Vandeleur-Lynams & the Arderins, and updated in 2015. In 2023, the MountainView Online Database listed 409 Irish mountains as meeting the Arderin definition. Several of the MountainViews.ie users have recorded completing the entire list of Arderins. One user having completed the Arderins within one single year (2014) along with the complete list of Vandeleur-Lynams, county highpoints and the highest 100 list.

MountainViews uses the term Arderin Begs for the additional class of peaks over {{convert|500|m|0|abbr=on}} in height, and with a prominence between {{convert|15-30|m|0|abbr=on}}. In 2018, Ireland had 124 Arderin Begs.{{cite web|url=https://mountainviews.ie/lists/arderinall/|title=Arderins + Arderin Begs: Irish mountains of 500+m with a prominence of 15+m|publisher=MountainViews|author=Simon Stewart|date=2018|quote=Listing selection: All summits (531) in list Arderins + Arderin Begs}}