U.S. Route 12 in Washington#Early years

File:US 12 Aberdeen bridge.jpg near Aberdeen]]

US 12 begins in downtown Aberdeen on the Pacific Coast as a pair of one-way streets: Heron Street for eastbound traffic and Wishkah Street for westbound traffic. The streets travel from the highway's western terminus at US 101, which continues west to Hoquiam and south to Cosmopolis, across the Wishkah River and merge onto Wishkah Street near a shopping center. US 12 leaves Aberdeen and follows the Chehalis River east through Central Park as a four-lane divided highway. The highway bypasses the towns of Montesano and Elma, which are served by interchanges as well as a junction with SR 107 in the former.{{google maps |title=U.S. Route 12 in Washington |url=https://www.google.com/maps/dir/46.9746799,-123.8146893/46.4204363,-117.0359002/@45.7836706,-121.4774162,7z/am=t/data=!3m1!4b1!4m14!4m13!1m10!3m4!1m2!1d-121.2235751!2d46.643633!3s0x54973f2663680ccf:0xc0114a9960c34097!3m4!1m2!1d-118.5627255!2d46.0538365!3s0x54a26641859a7ad3:0x81a3cc42700eee5d!1m0!3e0 |accessdate=August 1, 2022}}

In Elma, US 12 exits at a diamond interchange, while the highway continues east to Olympia as SR 8. US 12 heads southeast towards Oakville and Rochester, still following the Chehalis River.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=108 |section=H4 |isbn=0-528-93961-0}}{{cite map |publisher=GM Johnson |title=Port Angeles, Port Townsend, Sequim, Aberdeen, Hoquiam |year=2006 |section=C32 |isbn=0-528-95736-8}} East of Oakville, US 12 runs north of the Chehalis Indian Reservation.{{cite map |publisher=Rand McNally |title=The Thomas Guide Pacific Northwest Road Atlas |year=2006 |edition=7th |page=117 |section=B1 |isbn=0-528-85869-6}} It then continues east through the town of Rochester, and interchanges with I-5 at exit 88 in the town of Grand Mound.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=108 |section=I6 |isbn=0-528-93961-0}}

File:Riffe Lake.jpgUS 12 continues south concurrent with I-5 through Chehalis and Centralia before exiting again at exit 68 south of Napavine.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=108 |section=J6 |isbn=0-528-93961-0}} The highway then heads east along the Cowlitz River and passes through the town of Mossyrock, where it intersects SR 122. East of Mossyrock, US 12 runs just north of Mossyrock Dam and Riffe Lake. In the town of Morton, it intersects SR 7, which heads north to Tacoma.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=108 |section=J7 |isbn=0-528-93961-0}} It then ascends the Cascade Range, passing south of Mount Rainier, and intersects SR 123, which serves the Stevens Canyon entrance of Mount Rainier National Park.{{cite web |url=https://www.nps.gov/mora/planyourvisit/directions.htm |title=Mount Rainier National Park: Directions |access-date=March 20, 2008 |author=U.S. National Park Service}} {{convert|12|mi|km}} east of this intersection, US 12 crosses the Cascades over White Pass at an elevation of {{convert|4500|ft|m|sigfig=4}}.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=108 |section=I9 |isbn=0-528-93961-0}} White Pass is the only crossing of the Cascades open year-round between I-90 over Snoqualmie Pass and SR 14 through the Columbia River Gorge.{{cite web |url=http://www.wsdot.wa.gov/traffic/passes/ |title=WSDOT: Mountain Passes |author=Staff |publisher=Washington State Department of Transportation |year=2007 |access-date=April 18, 2008}}

After it descends the mountains, US 12 intersects SR 410 (formerly US 410) west of Naches, which serves Chinook Pass, Cayuse Pass, and the White River entrance of Mount Rainier National Park. East of Naches, US 12 widens once again to four lanes as it approaches the city of Yakima. There, it has an interchange with I-82 and US 97 at exit 31.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=109 |section=J12, M20 |isbn=0-528-93961-0}} US 12 then runs concurrently with I-82, bypassing the towns of Toppenish and Prosser and paralleling the Yakima River, until exit 102 near the Tri-Cities. At exit 102, it meets the western terminus of Interstate 182. US 12 and I-182 then run concurrently east over Goose Gap and through the Tri-Cities. In Pasco, I-182 ends, and US 12 intersects US 395.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=109 |section=K15 |isbn=0-528-93961-0}}

File:U.S. Route 12 eastbound at State Route 127 in Dodge, WA.jpg in rural Garfield County]]

US 12 then heads south to the town of Wallula, intersecting US 730, then east to Walla Walla, north to Dodge, and east to Clarkston before crossing the Idaho state line over the Snake River just outside Lewiston.{{cite map |publisher=Rand McNally |title=The Road Atlas |year=2008 |page=109 |section=K15, J20 |isbn=0-528-93961-0}} US 12 through Walla Walla consists of a four-lane bypass, also known as Inland Empire Highway.{{cite map |publisher=Rand McNally |title=The Thomas Guide Pacific Northwest Road Atlas |year=2006 |edition=7th |page=344–345 |isbn=0-528-85869-6}} The alignment of US 12 through Walla Walla County passes by a number of historical landmarks,{{cite news |work=Walla Walla Union-Bulletin |title=A Highway Gain |date=December 31, 1967 |page=4}} such as Whitman Mission and Fort Walla Walla.

The Washington section of US 12 was originally developed as a state highway in the early 20th century. It was incorporated into several later highways, including US 410.

File:SR 123 area history.svg

The Washington State Legislature created the State Highway Board in 1905 and appropriated funds to construct—but not maintain—twelve highways in sparsely settled areas of the state. Main highways in more populated areas would continue to be entirely under county control, though sometimes built with 50% state aid. Six of these highways were east-west crossings of the Cascades, including one in the corridor currently served by U.S. Route 12—State Road 5, the Cowlitz Pass State Road, climbing east from a point near Salkum via the Cowlitz River, over Cowlitz Pass, and down towards Yakima.{{cite WAstat |year=1905 |ch=7 |p=21}}: "(5) For the building of a State wagon road in Yakima and Lewis Counties, as follows, to-wit: Beginning at a point in the center of the public highway running from the town of Napavine to Klickitat prairie in Lewis County, Washington, at the point nearest to the south-east corner of Section 10 in Township 12, north of Range 1, east of Willamette meridian, and running thence by way of Klickitat prairie and Riffe Postoffice in a generally easterly course up the Cowlitz river and its tributaries to the summit of the Cascade mountains at the Cowlitz pass, thence easterly towards the town of North Yakima to a point in Yakima County, intersecting with a public highway leading to the town of North Yakima, said road to be known and designated as the Cowlitz Pass State road, the sum of $26,000."{{cite report |author=Staff |publisher=Washington Department of Transportation |url=http://www.wsdot.wa.gov/NR/rdonlyres/AFDDA538-123B-43F8-A166-B30BAA34C492/0/40yearsReport.pdf |title=Forty Years with the Washington Department of Highways |pages=1–2, 6 |access-date=March 1, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20081030044027/http://www.wsdot.wa.gov/NR/rdonlyres/AFDDA538-123B-43F8-A166-B30BAA34C492/0/40yearsReport.pdf |archive-date=October 30, 2008 }} A 1907 amendment renamed State Road 5 the Cowlitz-Natches Road, moved the Cascade crossing north to Carlton Pass, and defined the portion east of the pass to follow the Bumping River and Naches River to a point near Naches. East of the mouth of the American River, this replaced part of State Road 1 (North Yakima and Natches State Road), which had been defined in 1897 to cross the Cascades north of Chinook Pass{{cite WAstat |year=1897 |ch=116 |p=342}} and included in the 1905 appropriations.{{cite WAstat |year=1907 |ch=151 |p=310}}: "State Road No. 5, or the Cowlitz-Natches road: This road shall begin at a point in the center of the public highway running from the town of Napavine to Klickitat prairie in Lewis county, Washington, at the point nearest to the southeast corner of section 10, in township 12, north of range 1 east W. M., and shall run thence over the present surveyed line on such state road, by the way of Klicitat[sic] prairie and Riffe postoffice up the Cowlitz river and its tributaries, and over the summit of the Cascade mountains at the Carlton pass; thence over such surveyed line for said road down Bumping river and the Natches river to a point which bears south 73 degrees and 24 minutes east and is {{convert|2356|ft|m}} distant from the corner of sections 27, 28, 33 and 34, in township 15, north range 16, east W. M., in Yakima county, Washington."

Under a 1909 law, the State Highway Board surveyed a connected network of proposed state roads. Included was a westerly extension of SR 5 via Chehalis to South Bend and Aberdeen and an easterly extension to Pullman. A route from Yakima southeast and east via the Tri-Cities to Idaho was also surveyed, mostly as an extension of State Road 8 (Columbia River Road).{{cite WAstat |year=1909 |ch=51 |p=95}}: "2nd. Extension over the most feasible route of State Road No. 5 westerly through the city of Chehalis to the cities of South Bend in Pacific county and Aberdeen in Chehalis county, and easterly to the city of Pullman in Whitman county." "3rd. Extension over the most feasible route of State Road No. 8 westerly to the city of Vancouver and easterly to the city of Walla Walla and thence to the eastern boundary of Asotin county." "6th. A road beginning at a point on the proposed extension of State Road No. 7 in the vicinity of Cle Elum in Kittitas county, leading thence as nearly as practicable along the Yakima valley to an intersection with the proposed extension of State Road No. 8 in Benton county." The legislature added most of these routes to the state highway system in 1913, when they formed a two-tiered system of primary and secondary roads. Primary roads were completely controlled by the state, including maintenance, and received only names, while secondary roads kept their numbers and county maintenance. The National Park Highway replaced State Road 5 west of Riffe, and extended as surveyed to and beyond South Bend, and the McClellan Pass Highway replaced State Road 1 and continued via State Road 5 to Yakima. The majority of the route from Yakima via Connell to Pullman was not added at that time; it was finally taken over in 1937 as Secondary State Highways 11A and 11B. Only the route via the Tri-Cities, forming part of the Inland Empire Highway, continued from Yakima to Idaho. East of Pomeroy, the original survey had curved south, using State Road 16 to near the Oregon state line; this was bypassed by the 1913 designation, which instead continued directly east to Clarkston. Unlike the earlier state roads, these primary roads mostly followed existing passable county roads.{{cite map |publisher=State Highway Board |url=http://www.secstate.wa.gov/history/maps_detail.aspx?m=33 |title=Road Map of Washington Showing Main Traveled Roads |year=1912 |access-date=March 27, 2008}} The incomplete roadway between Riffe and the American River remained as part of secondary State Road 5, and the legislature designated the surveyed route from the National Park Highway near Raymond north to Aberdeen as secondary State Road 20 in 1915.{{cite map |publisher=State Highway Board |url=http://www.secstate.wa.gov/history/maps_detail.aspx?m=38 |title=Map of the State of Washington Showing State Roads: Located and Proposed |year=1909 |access-date=March 27, 2008}}{{cite WAstat |year=1913 |ch=65 |p=221-223}}{{cite WAstat |year=1915 |ch=164 |p=491}}{{cite map |publisher=State Highway Board |url=http://www.secstate.wa.gov/history/maps_detail.aspx?m=27 |title=State of Washington Showing State Highways Authorized by Legislative Acts of 1915 |access-date=March 27, 2008}}

File:White Pass.jpg

A 1923 restructuring of the system reassigned numbers to almost all the primary state highways. State Road 5 became a primary route and was greatly expanded, taking over the entire McClellan Pass Highway and the National Park Highway east of the Pacific Highway. The former secondary State Road 5 was realigned starting from near Packwood, heading north instead of east, alongside the Ohanapecosh River to the old McClellan Pass Highway at Cayuse Pass, west of the summit of the Cascades. The new State Road 5, named the National Park Highway System, now included four roads in the vicinity of Mount Rainier National Park, but as the road across the Cascades at Chinook Pass was not yet built, these roads did not connect with each other.{{cite map |publisher=Rand McNally |url=http://www.broermapsonline.org/members/NorthAmerica/UnitedStates/Northwest/Washington/unitedstates1926ra_076.html |title=Auto Road Atlas |year=1926 |access-date=April 9, 2008 |archive-date=March 31, 2008 |archive-url=https://web.archive.org/web/20080331200956/http://www.broermapsonline.org/members/NorthAmerica/UnitedStates/Northwest/Washington/unitedstates1926ra_076.html |url-status=dead }} Also included in this numbering was the designation of the Inland Empire Highway, including Yakima to Clarkston, as State Road 3.{{cite WAstat |year=1923 |ch=185 |p=628-629}}: "A primary state highway, to be known as State Road No. 5 or the National Park Highway System, is established as follows: Beginning at the City of Tacoma; thence by the most feasible route in a southeasterly direction through Elbe and Ashford to the Rainier National Park gate; also from a junction in the City of Elbe; thence in a southerly direction through Morton, Kosmos; thence in a westerly direction through Nesika, Riffe and Ethel to a junction with State Road No. 1 or the Pacific Highway at or in the vicinity of Jackson Prairie; also, from a junction at or near Kosmos in Lewis County in a northeasterly direction through Lewis in Lewis County through Sheepskull Gap; thence in a northwesterly direction through Enumclaw, Auburn, Kent to a connection with State Road No. 2 in the vicinity of Renton; also from a junction at Sheepskull Gap in a southeasterly direction to Yakima." In 1925, a spur was added to State Road 9—the Olympic Highway, looping around the Olympic Peninsula—connecting Elma to the Pacific Highway at Grand Mound, and creating a shortcut between the Cowlitz River route and Aberdeen.{{cite WAstat |year=1925 |ch=26 |p=58-59}} The Olympic Highway from Elma west to Aberdeen had been added to the state highway system in 1905 west of and 1913 east of Montesano.

File:U.S. Route 12 in Washington (35017966625).jpg of the Interstate Highway Bridge (built in 1939), with Lewiston, Idaho in the background. This bridge carries U.S. Route 12 between Washington State and Idaho.]]As part of the U.S. Highway system laid out in 1925 and finalized in late 1926, US 410 connected Aberdeen with Clarkston, following the Olympic Highway (State Road 9) to Olympia, the Pacific Highway (State Road 1)—concurrent with US 99—to Tacoma, the National Park Highway System (State Road 5) to Yakima, and the Inland Empire Highway (State Road 3) to Clarkston.{{cite map |author1= Bureau of Public Roads |author2= American Association of State Highway Officials |date= November 11, 1926 |title= United States System of Highways Adopted for Uniform Marking by the American Association of State Highway Officials |url= https://commons.wikimedia.org/wiki/File:United_States_System_of_Highways_Adopted_for_Uniform_Marking_by_the_American_Association_of_State_Highway_Officials.jpg |scale= 1:7,000,000 |location= Washington, DC |publisher= United States Geological Survey |oclc= 32889555 |access-date= November 7, 2013 |via= Wikimedia Commons |name-list-style= amp}} This differed from present US 12 between Elma and Naches in that it followed the route through Olympia and Tacoma rather than along the Cowlitz River. However, despite being part of the state highway system since 1897, US 410's crossing of the Cascades, the first between the Columbia River Gorge and Snoqualmie Pass, was not opened to traffic until 1931.{{cite book |publisher=National Park Service |url=http://www.nps.gov/archive/mora/adhi/adhi8.htm |archive-url=https://web.archive.org/web/20070112200805/http://www.nps.gov/archive/mora/adhi/adhi8.htm |url-status=dead |archive-date=January 12, 2007 |title=Mount Rainier: Administrative History |chapter=Chapter 8: The Park Under Construction |access-date=March 1, 2008}} The new highway, named the Mather Memorial Highway for conservationist Stephen Mather, was dedicated on July 2, 1932.{{cite news |date=July 1, 1932 |title=Two Ceremonies to Honor Mather |page=2 |work=The Tacoma News Tribune |url=https://www.newspapers.com/article/the-news-tribune-two-ceremonies-to-honor/129093938/ |via=Newspapers.com |accessdate=July 29, 2023}}{{cite news |date=August 10, 1932 |title=Cascade's Wondaland Within One Day of City |page=13 |work=Spokane Daily Chronicle |url=https://www.newspapers.com/article/spokane-chronicle-cascades-wondaland-wi/129094007/ |via=Newspapers.com |accessdate=July 29, 2023}} A shortcut from near Packwood east across White Pass to Naches, very close to the original plan for the east half of State Road 5, was added to the state highway system in 1931 as another branch of the highway.{{cite map |publisher=Department of Highways |url=http://www.secstate.wa.gov/history/maps_detail.aspx?m=34 |title=Highway Map: State of Washington |date=June 12, 1931 |access-date=March 27, 2008}} The roadway between Packwood and Cayuse Pass, added to the state highway system on a different alignment in 1905, was finally completed in 1940,{{cite book |publisher=National Park Service |url=http://www.nps.gov/archive/mora/adhi/adhi11a.htm |archive-url=https://web.archive.org/web/20070114210728/http://www.nps.gov/archive/mora/adhi/adhi11a.htm |url-status=dead |archive-date=January 14, 2007 |title=Mount Rainier: Administrative History |chapter=Chapter 11: The Impact of the New Deal |access-date=March 1, 2008}} and the White Pass Highway was dedicated on August 12, 1951, opening a shortcut between southwest Washington and Yakima.{{cite news |work=Walla Walla Union-Bulletin |title=White Pass Road Formal Dedication on August 12 |date=July 18, 1951 |page=7}}

When the U.S. Highways were first established in 1926, US 12 ended in Miles City, Montana, and most of US 12's current routing in Washington was followed by US 410. U.S. Route 12 was extended westward in stages; an extension to Lewiston, Idaho, was approved on June 19, 1962. At various times in the early 1960s, the states of Idaho, Washington, and Oregon submitted plans for further westward extension to the American Association of State Highway Officials (AASHO) to either Vancouver, Washington or Boardman, Oregon—or, a plan submitted in 1963 had the highway going only as far as Pasco—but all of these plans were rejected.{{AASHTO minutes |year=1962A |page=12 |access-date=April 2, 2021}} Washington introduced a new system of sign route numbers in 1964. While US 410 was still signed as such, present US 12 became State Route 8 between US 410 at Elma and US 99/I-5 at Grand Mound and State Route 14 between US 99/I-5 at Chehalis and US 410 at Naches.{{cite web |author=Staff |publisher=Washington State Highway Commission |title=Identification of State Highways |url=https://www.wsdot.wa.gov/sites/default/files/2005/04/26/Identification-of-state-highways.pdf |date=December 1, 1965 |access-date=March 20, 2008 |archive-date=February 17, 2017 |archive-url=https://web.archive.org/web/20170217112902/https://www.wsdot.wa.gov/NR/rdonlyres/6836215D-E301-43F3-895A-472BD2FDE86A/0/Identification.pdf |url-status=dead }}

The extension of US 12 to Aberdeen was approved on June 20, 1967, with US 12 taking over much of US 410's former routing.{{cite web |url=https://www.fhwa.dot.gov/infrastructure/us12.cfm |title=U.S. 12 Michigan to Washington |access-date=March 20, 2008 |last=Weingroff |first=Richard F. |date=May 7, 2005 |publisher=Federal Highway Administration}}{{cite news |date=December 31, 1967 |title=Route 410 Renamed Highway 12 |page=1 |work=Tri-City Herald |url=https://www.newspapers.com/clip/106332102/route-410-renamed-highway-12/ |via=Newspapers.com |accessdate=July 25, 2022}} However, where US 410 had crossed the Cascades at Chinook Pass, US 12 used the all-weather White Pass, replacing SR 8 and SR 14.{{cite news |work=Walla Walla Union-Bulletin |title=All-Weather Plan Picked By Highway Commission |date=April 23, 1967 |page=5}} Signs were changed in late December 1967,{{cite news |work=Walla Walla Union-Bulletin |title=Highway 410 is now U.S. No. 12 |date=December 28, 1967 |page=1}} and the bypassed segments of US 410 became a new SR 8 between Elma and Olympia, and SR 410 between Tacoma and Naches.{{cite news |title=U-B Action Line |work=Walla Walla Union-Bulletin |date=September 29, 1968 |page=1}}{{cite report |url=http://www.wsdot.wa.gov/mapsdata/tdo/PDF_and_ZIP_Files/1970_ATR.pdf |author=Staff |publisher=Washington State Highway Commission |title=Annual Traffic Report |year=1970 |access-date=April 23, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080625093148/http://www.wsdot.wa.gov/mapsdata/tdo/PDF_and_ZIP_Files/1970_ATR.pdf |archive-date=June 25, 2008 }} Due to construction of the Mossyrock Dam on the Cowlitz River, which would create Riffe Lake and inundate parts of the valley, US 12 was relocated in December 1967 on a {{convert|16|mi|km|adj=mid}} route that traveled through Morton.{{cite news |date=December 3, 1967 |title=New Highway Bypasses New Reservoir |page=B14 |work=The Tacoma News Tribune |url=https://www.newspapers.com/article/the-news-tribune-new-highway-bypasses-ne/129114786/ |via=Newspapers.com |accessdate=July 29, 2023}} The detour was opened early after the Nesika Bridge over the Cowlitz River was destroyed in a fire started accidentally by construction crews a month earlier.{{cite news |date=November 3, 1967 |title=New Mossyrock Detour Will Be Opened Early |page=1 |work=The Daily Chronicle |url=https://www.newspapers.com/article/the-daily-chronicle-new-mossyrock-detour/129114710/ |via=Newspapers.com |accessdate=July 29, 2023}} The final project near the dam, a {{convert|1,136|ft|m|adj=mid}} arch bridge over the Cowlitz River, opened in May 1968 and was primarily financed by Tacoma City Light; at the time, it was the longest concrete arch bridge in North America.{{cite news |date=May 1, 1968 |title=New Cowlitz River Bridge Opens Friday |page=A4 |work=The Tacoma News Tribune |url=https://www.newspapers.com/article/the-news-tribune-new-cowlitz-river-bridg/129114980/ |via=Newspapers.com |accessdate=July 29, 2023}}{{cite news |date=May 1968 |title=Record-Breaking Cowlitz Span Opens |page=15 |work=Washington Highway News |volume=18 |issue=3 |publisher=Washington State Department of Highways |oclc=29654162 |url=https://cdm16977.contentdm.oclc.org/digital/collection/p16977coll1/id/5372/ |via=WSDOT Library Digital Collections |accessdate=July 29, 2023}}

The Montesano–Elma section of US 12 was moved to a new, {{convert|9|mi|km|adj=mid}} divided highway in February 1969 after construction was completed on the last section of the Ocean Freeway.{{cite news |date=February 9, 1969 |title=Dedication Reset For Highway |page=B7 |work=The Tacoma News Tribune |url=https://www.newspapers.com/article/the-news-tribune-dedication-reset-for-hi/129084988/ |via=Newspapers.com |accessdate=July 29, 2023}} Construction of a {{convert|6.5|mi|km|adj=mid}} freeway to bypass downtown Walla Walla began in 1971 and was completed three years later at a cost of $13 million—about $5 million over the original estimate due to inflation.{{cite news |last=Cockle |first=Dick |date=February 24, 1974 |title=New freeway adds to safety, convenience |page=18F |work=Walla Walla Union-Bulletin |url=https://newspaperarchive.com/other-articles-clipping-feb-24-1974-3993596/ |via=NewspaperArchive.com |accessdate=July 26, 2023}} The freeway opened on October 17, 1973, despite local opposition that compared the elevated overpasses to the Berlin Wall.{{cite news |last=Jenkins |first=Sarah |date=February 24, 1985 |title=WW's 'Berlin Wall' |page=E4 |work=Walla Walla Union-Bulletin}} In 1985, US 12 was moved onto I-182 in the Tri-Cities, while its former route through Kennewick was replaced with an extension of SR 240.{{cite news |date=April 12, 1985 |title=New numbers for old roads |page=B1 |work=Tri-City Herald |url=https://www.newspapers.com/article/tri-city-herald-new-numbers-for-old-road/106333876/ |via=Newspapers.com |accessdate=July 26, 2023}} The change was not formally submitted to the AASHTO until 2006.{{AASHTO minutes |year=2006A |accessdate=November 26, 2021}} The White Pass Scenic Byway was designated as a National Scenic Byway in October 2009.{{cite news |last=Richard |first=Terry |date=October 22, 2009 |title=White Pass gets byway designation, as well as biggest on-going ski area project in Northwest |url=https://www.oregonlive.com/terryrichard/2009/10/white_pass_expansion_under_way.html |work=The Oregonian |accessdate=November 7, 2022}}

Local officials in Walla Walla County began lobbying for the replacement of two-lane sections on US 12 between the Tri-Cities and Walla Walla with a four-lane divided highway in the 1970s. The project was funded by the state government in 2001 and broken up into eight phases, of which six were completed between 2004 and 2012 at a cost of $180 million.{{cite news |last=Smith |first=Katie |date=May 26, 2023 |title=New stretch of US 12 north of Lowden and Touchet set to open Friday afternoon |url=https://www.union-bulletin.com/news/local/governments/new-stretch-of-us-12-north-of-lowden-and-touchet-set-to-open-friday-afternoon/article_a5a82a50-fb4c-11ed-a9d9-6bffa72eec22.html |work=Walla Walla Union-Bulletin |accessdate=May 31, 2023}}{{cite news |last=Joshi |first=Pratik |date=July 9, 2010 |title=Officials mark latest Highway 12 milestone |url=https://www.tri-cityherald.com/news/local/article31782069.html |work=Tri-City Herald |accessdate=May 31, 2023}} The seventh phase, bypassing Touchet and constructing {{convert|11|mi|km}} of four-lane highway with two interchanges, began construction in 2021 and opened to traffic on June 2, 2023.{{cite news |last=LeValley |first=Chloe |date=May 29, 2021 |title=Current phase of U.S. Highway 12 project nears 25% completion west of Walla Walla |url=https://www.union-bulletin.com/news/current-phase-of-u-s-highway-12-project-nears-25-completion-west-of-walla-walla/article_3721a03a-bfe8-11eb-9f4b-e3e2f92b9ff8.html |work=Walla Walla Union-Bulletin |access-date=March 10, 2022}}{{cite press release |date=June 6, 2023 |title=Season premiere: New segment of US 12 near Walla Walla opened Friday, June 2 |url=https://wsdot.wa.gov/about/news/2023/season-premiere-new-segment-us-12-near-walla-walla-opened-friday-june-2 |publisher=Washington State Department of Transportation |accessdate=June 6, 2023}} The original opening date of May 26 was delayed by a week after issues with a paint truck needed for road striping.{{cite news |last=Smith |first=Kate |date=June 2, 2023 |title=New stretch of US 12 between Walla Walla, Tri-Cities to open this afternoon |url=https://www.union-bulletin.com/news/local/governments/new-stretch-of-us-12-between-walla-walla-tri-cities-to-open-this-afternoon/article_53791ea8-0167-11ee-9967-c3c6fc73696e.html |work=Walla Walla Union-Bulletin |accessdate=June 6, 2023}} Construction of the final phase, bypassing Wallula Junction, remains unfunded {{as of|2022|lc=y}} and would require an extension of US 730 to a new interchange with US 12.{{cite web |date=March 2018 |title=Four-laning US Highway 12: Phase 7 – Nine Mile Hill to Frenchtown Vicinity |url=https://wsdot.wa.gov/sites/default/files/2018/03/15/US12Phase7folio.PDF |publisher=Washington State Department of Transportation |url-status=dead |archive-url=https://web.archive.org/web/20210513080622/https://wsdot.wa.gov/sites/default/files/2018/03/15/US12Phase7folio.PDF |archive-date=May 13, 2021 |access-date=April 2, 2021}}{{cite news |last=Dinman |first=Emry |date=July 1, 2022 |title=Phase 7 of U.S. Highway 12 project 70% done in Walla Walla County |url=https://www.union-bulletin.com/news/local/governments/phase-7-of-u-s-highway-12-project-70-done-in-walla-walla-county/article_663b1012-f981-11ec-83e5-f3209692c549.html |work=Walla Walla Union-Bulletin |accessdate=March 15, 2023}}

{{clear}}

{{Jcttop|exit|length_ref=}}

{{WAint|exit

|county=Grays Harbor

|cspan=5

|location=Aberdeen

|mile=0.00

|road={{jct|state=WA|US|101|to2=to|SR|105|SR|109|city1=Westport|city2=Grayland|city3=Raymond|city4=Port Angeles|city5=Hoquiam}}

}}

{{WAint|exit

|location=none

|mile=9.41

|road=Devonshire Road

}}

{{WAint|exit

|location=Montesano

|mile=10.24

|road={{jct|state=WA|SR|107|city1=Montesano|city2=Raymond}}

}}

{{WAint|exit

|location=Elma

|lspan=2

|mile=20.19

|road=3rd Street – Satsop Development Park

|notes=Interchange

}}

{{WAint|exit

|mile=20.99

|road={{jct|state=WA|SR|8|dir1=east|city1=Olympia}}

|notes=Interchange

}}

{{WAint|exit

|county=Thurston

|cspan=3

|location=Rochester

|mile=41.58

|road=Albany Street

|notes=Former SR 121

}}

{{WAint|exit

|location=Grand Mound

|lspan=2

|mile=46.07

|road=Old Highway 99 – Grand Mound

|notes=Former US 99 south

}}

{{WAint|exit

|mile=46.32

|type=concur

|exit=88

|road={{Jct|state=WA|I|5|dir1=North|road|Old Highway 99|city1=Seattle|city2=Tenino}}

|notes=Western end of I-5 concurrency; western end of freeway; former US 99 north

}}

{{WAint|exit

|county=Lewis

|cspan=15

|location=Centralia

|lspan=2

|mile=51.92

|exit=82

|road=Harrison Avenue / Factory Outlet Way

}}

{{WAint|exit

|mile=52.98

|exit=81

|road={{jct|state=WA|WA|507|name1=Mellen Street}}

|notes=Southbound exit is via exit 82.

}}

{{WAint|exit

|location=Chehalis

|lspan=4

|mile=55.57

|exit=79

|road=Chamber Way

}}

{{WAint|exit

|mile=56.68

|exit=77

|road={{jct|state=WA|WA|6|dir1=west|city1=Pe Ell|city2=Raymond}}

}}

{{WAint|exit

|mile=58.10

|exit=76

|road=13th Street

}}

{{WAint|exit

|mile=60.27

|exit=74

|road=Labree Road

}}

{{WAint|exit

|location=Napavine

|lspan=2

|mile=61.87

|exit=72

|road=Rush Road

}}

{{WAint|exit

|mile=63.60

|exit=71

|road={{jct|state=WA|WA|508|dir1=east|city1=Onalaska|city2=Napavine}}

}}

{{WAint|exit

|location=none

|mile=66.24

|type=concur

|exit=68

|road={{jct|state=WA|I|5|dir1=south|location1=Portland}}

|notes=Eastern end of I-5 concurrency; eastern end of freeway

}}

{{WAint|exit

|location=Mary's Corner

|mile=68.86

|road=Jackson Highway – Lewis and Clark State Park

|notes=Former US 99

}}

{{WAint|exit

|location=Silver Creek

|mile=79.98

|road={{jct|state=WA|SR|122|dir1=east}}

}}

{{WAint|exit

|location=Mossyrock

|mile=86.59

|road={{jct|state=WA|SR|122|dir1=west}}

}}

{{WAint|exit

|location=Morton

|mile=97.40

|road={{jct|state=WA|SR|7|dir1=north|city1=Morton|city2=Mount Rainier|city3=Tacoma}}

}}

{{WAint|exit

|location=Randle

|mile=114.72

|road={{jct|state=WA|SR|131|dir1=south|city1=Mount St. Helens|to2=to|FR|23|FR|25}}

}}

{{WAint|exit

|location=none

|mile=138.34

|road={{jct|state=WA|SR|123|dir1=north|city1=Mount Rainier National Park}}

}}

{{WAint|exit

|county1=Lewis

|county2=Yakima

|location=none

|mile=150.79

|place=White Pass

}}

{{WAint|exit

|county=Yakima

|cspan=23

|location=none

|mile=185.08

|road={{jct|state=WA|SR|410|dir1=west|location1=Chinook Pass}}

}}

{{WAint|exit

|location=none

|mile=199.06

|place=Western end of freeway

}}

{{WAint|exit

|location=Yakima

|lspan=7

|mile=199.64

|road=Fruitvale Boulevard, North 40th Avenue

}}

{{WAint|exit

|mile=201.25

|road=North 16th Avenue

}}

{{WAint|exit

|mile=202.19

|road=North 1st Street

}}

{{WAint|exit

|mile=202.44

|type=concur

|exit=31

|road={{jct|state=WA|I|82|dir1=west|US|97|dir2=north|city1=Selah|city2=Ellensburg|name2=SR 823 north}}

|notes=Western end of I-82 and US 97 concurrencies

}}

{{WAint|exit

|mile=203.72

|type=incomplete

|exit=33A

|road=Fair Avenue, Lincoln Avenue

|notes=Eastbound exit only

}}

{{WAint|exit

|mile=204.27

|exit=33B

|road=Yakima Avenue – Terrace Heights

|notes=Signed as exit 33 westbound

}}

{{WAint|exit

|mile=205.80

|exit=34

|road={{Jct|state=WA|SR|24|dir1=east|road|Nob Hill Boulevard|city1=Moxee}}

}}

{{WAint|exit

|location=Union Gap

|mile=207.32

|exit=36

|road=Valley Mall Boulevard – Union Gap

}}

{{WAint|exit

|location=none

|mile=208.87

|type=concur

|exit=37

|road={{Jct|state=WA|US|97|dir1=south|city1=Goldendale|location=Bend, Ore.}}

|notes=Eastern end of US 97 concurrency; eastbound exit and westbound entrance

}}

{{WAint|exit

|location=none

|mile=209.13

|type=incomplete

|exit=38

|road=Union Gap

|notes=Westbound exit and eastbound entrance

}}

{{WAint|exit

|location=none

|mile=211.37

|exit=40

|road=Thorp Road, Parker Road

}}

{{WAint|exit

|location=none

|mile=215.35

|exit=44

|road=Wapato

}}

{{WAint|exit

|location=none

|mile=221.14

|exit=50

|road={{jct|state=WA|SR|22|dir1=east|city1=Toppenish|city2=Buena}}

}}

{{WAint|exit

|location=Zillah

|lspan=2

|mile=223.11

|exit=52

|road=Zillah, Toppenish

}}

{{WAint|exit

|mile=225.11

|exit=54

|road=Division Road – Zillah

}}

{{WAint|exit

|location=Granger

|mile=229.53

|exit=58

|road={{jct|state=WA|SR|223|dir1=south|city1=Granger}}

}}

{{WAint|exit

|location=Outlook

|mile=234.67

|exit=63

|road=Sunnyside, Outlook

}}

{{WAint|exit

|location=Sunnyside

|lspan=2

|mile=237.96

|exit=67

|road=Sunnyside, Mabton

}}

{{WAint|exit

|mile=239.97

|exit=69

|road={{jct|state=WA|SR|241|location1=Vernita Bridge|city2=Sunnyside|city3=Mabton}}

}}

{{WAint|exit

|location=Grandview

|lspan=2

|mile=243.64

|exit=73

|road=Stover Road – Grandview

}}

{{WAint|exit

|mile=246.08

|exit=75

|road=County Line Road – Grandview

}}

{{WAint|exit

|county=Benton

|cspan=9

|location=Prosser

|lspan=2

|mile=250.96

|exit=80

|road={{jct|state=WA|CR|12|county1=Benton|name1=Wine Country Road|road|Gap Road|city1=Prosser}}

}}

{{WAint|exit

|mile=253.37

|exit=82

|road={{jct|state=WA|SR|22|to2=to|SR|221|city1=Mabton|city2=Paterson}}

}}

{{WAint|exit

|location=none

|mile=259.58

|exit=88

|road=Gibbon Road

}}

{{WAint|exit

|location=none

|mile=264.64

|exit=93

|road=Yakitat Road

}}

{{WAint|exit

|location=Benton City

|mile=267.61

|exit=96

|road={{Jct|state=WA|SR|224|dir1=east|SR|225|dir2=north|city1=West Richland|city2=Benton City}}

}}

{{WAint|exit

|location=none

|mile=273.62

|type=concur

|exit=102

|road={{jct|state=WA|I|82|dir1=east|location1=Umatilla|location2=Pendleton}}
{{Jct|state=WA|I|182|dir1=east|city1=Richland|city2=Pasco}}

|notes=Eastern end of I-82 concurrency; western end of I-182 concurrency; exit 102 on I-82 eastbound, unnumbered exit on I-182 westbound

}}

{{WAint|exit

|location=Richland

|lspan=3

|mile=276.55

|exit=3

|road=Queensgate Drive

|notes=Signed as exits 3A (south) and 3B (north) westbound

}}

{{WAint|exit

|mile=277.45

|type=concur

|exit=4

|road={{Jct|state=WA|SR|240|dir1=west|road|Wellsian Way|city1=Vantage}}

|notes=Western end of SR 240 concurrency

}}

{{WAint|exit

|mile=278.57

|type=concur

|exit=5

|road={{Jct|state=WA|SR|240|dir1=east|name1=George Washington Way|city1=Kennewick}}

|notes=Eastern end of SR 240 concurrency; signed as exits 5A (south) and 5B (north)

}}

{{Jctbridge|exit

|river=Columbia River

|mile=279.66

|bridge=Interstate 182 Bridge

}}

{{WAint|exit

|county=Franklin

|cspan=9

|location=Pasco

|lspan=9

|mile=280.93

|exit=7

|road=Broadmoor Boulevard

}}

{{WAint|exit

|mile=282.95

|exit=9

|road=Road 68

}}

{{WAint|exit

|mile=285.86

|type=concur

|exit=12A

|road={{Jct|state=WA|US|395|dir1=south|city1=Kennewick|location2=Pendleton}}

|notes=Western end of US 395 concurrency

}}

{{WAint|exit

|mile=286.30

|exit=12B

|road=North 20th Avenue – Columbia Basin College

}}

{{WAint|exit

|mile=287.38

|exit=13

|road=North 4th Avenue – Pasco City Center

}}

{{WAint|exit

|mile=287.99

|type=concur

|exit=14

|road={{Jct|state=WA|US|395|dir1=north|SR|397|dir2=south|name2=Oregon Avenue|city1=Spokane|city2=Finley}}

|notes=Eastern end of US 395 concurrency; signed as exits 14A (south) and 14B (north)

}}

{{WAint|exit

|mile=288.85

|type=concur

|road={{Jct|state=WA|I|182|dir1=ends}}

|notes=Eastern end of I-182 concurrency

}}

{{WAint|exit

|mile=289.57

|road=East Lewis Street – Kahlotus

}}

{{WAint|exit

|mile=290.80

|place=Eastern end of freeway

}}

{{WAint|exit

|county=Walla Walla

|cspan=10

|location=Burbank

|mile=292.58

|road={{jct|state=WA|SR|124|dir1=east|city1=Prescott|city2=Waitsburg}}

|notes=Interchange

}}

{{WAint|exit

|location=none

|mile=304.66

|road={{jct|state=WA|US|730|dir1=west|location1=Umatilla|location2=Pendleton}}

}}

{{WAint|exit

|location=none

|mile=315.19

|road=Old Highway 12 – Touchet

|notes=Interchange

}}

{{WAint|exit

|location=none

|mile=321.46

|road=Lower Dry Creek Road

|notes=Interchange

}}

{{WAint|exit

|location=Walla Walla

|lspan=5

|mile=332.17

|road={{jct|state=WA|SR|125|name2=via SR 125 Spur|to2=to|OR|11|city1=Prescott|location2=Pendleton}}

|notes=Interchange

}}

{{WAint|exit

|mile=333.47

|road=2nd Avenue – Walla Walla City Center

|notes=Interchange

}}

{{WAint|exit

|mile=334.76

|road=Rees Avenue

|notes=No access across US 12

}}

{{WAint|exit

|mile=336.66

|road=Airport Road – Port of Walla Walla, Walla Walla Regional Airport

|notes=Interchange

}}

{{WAint|exit

|mile=338.16

|road=Isaacs Avenue

|notes=Interchange

}}

{{WAint|exit

|location=Waitsburg

|mile=354.01

|road={{jct|state=WA|SR|124|dir1=west|city1=Prescott}}

}}

{{WAint|exit

|county=Columbia

|cspan=2

|location=none

|mile=369.09

|road=Turner Road

|notes=Former SR 126 east

}}

{{WAint|exit

|location=none

|mile=378.64

|road={{jct|state=WA|SR|261|dir1=north}}

}}

{{WAint|exit

|county=Garfield

|cspan=3

|location=none

|mile=387.22

|road={{jct|state=WA|SR|127|dir1=north|city1=Colfax|city2=Spokane}}

}}

{{WAint|exit

|location=none

|mile=394.45

|road=Marengo Road

|notes=Former SR 126 west

}}

{{WAint|exit

|location=Pomeroy

|mile=400.36

|road=15th Street

|notes=Former SR 128 east

}}

{{WAint|exit

|county=Asotin

|cspan=3

|location=Clarkston

|lspan=3

|mile=428.96

|road={{jct|state=WA|SR|128|dir1=east|to2=to|SR|193|location1=North Lewiston}}

}}

{{WAint|exit

|mile=430.34

|road={{jct|state=WA|SR|129|dir1=south|city1=Asotin}}

}}

{{WAint|exit

|mile=430.40

|road=1st Street – Port of Clarkston

}}

{{Jctbridge|exit

|river=Snake River

|lspan=2

|mile=430.52

|mspan=2

|bridge=Washington–Idaho state line (Lewiston–Clarkston Bridge)

}}

{{IDint|exit

|mile=none

|road={{Jct|state=ID|US|12|dir1=east|city1=Lewiston}}

|notes=Continuation into Idaho

}}

{{Jctbtm|exit|keys=concur,incomplete}}

{{Portal|U.S. roads|United States}}

{{-}}

{{reflist}}

{{Attached KML|display=title,inline}}

{{commons category|U.S. Route 12 in Washington (state)}}

{{Wikivoyage|Lewis and Clark Trail}}

• [https://www.angelfire.com/wa2/hwysofwastate/us012.html Highways of Washington State]

{{state detail page browse|type=US|route=12|state=Washington|stateafter=Idaho}}

{{State highways in Washington related to US 12}}

{{good article}}

{{DEFAULTSORT:U.S. Route 012 in Washington}}

12

Washington

012

Category:Transportation in Grays Harbor County, Washington

Category:Transportation in Thurston County, Washington

Category:Transportation in Lewis County, Washington

Category:Transportation in Yakima County, Washington

Category:Transportation in Benton County, Washington

Category:Transportation in Franklin County, Washington

Category:Transportation in Walla Walla County, Washington

Category:Transportation in Columbia County, Washington

Category:Transportation in Garfield County, Washington

Category:Transportation in Asotin County, Washington

Category:Gifford Pinchot National Forest