{{Short description|State highway in King County, Washington, US}} {{Use American English|date=May 2025}} {{Use mdy dates|date=December 2015}} {{Infobox road |state=WA |type=SR |route=599 |spur_type=I |spur_of=5 |section=808 |map=Washington State Route 599 Map.svg |map_notes=Map of King County in western Washington with SR&nbsp;599 highlighted in red |length_mi=1.75 |length_round=2 |length_ref=<ref name="log">{{WSDOT State Highway Log |year=2017 |pages=1662–1663 |link=yes |accessdate=December 23, 2018}}</ref> |established=1971 |direction_a=South |terminus_a={{jct|state=WA|I|5}} in Tukwila |direction_b=North |terminus_b={{jct|state=WA|SR|99}} in Tukwila |county=King |previous_type=SR |previous_route=548 |next_type=SR |next_route=702 }}

'''State Route&nbsp;599''' ('''SR&nbsp;599''') is a state highway and freeway in King County, Washington, United States. It is located entirely within the city of Tukwila and travels {{convert|1.75|mi|km|2}} northwest along the Duwamish River between junctions with Interstate&nbsp;5 (I-5) and SR&nbsp;99. The freeway has one intermediate exit and follows the Link light rail 1 Line.

==Route description== thumb|Traffic on SR 599 after dark SR&nbsp;599 is {{convert|1.75|mi|km|2}} long and travels on a four-lane freeway located entirely within the city of Tukwila in suburban King County.<ref name="log"/> It begins at a Y interchange with I-5 near Foster Memorial Park, approximately {{convert|1.4|mi|km|1}} north of the Southcenter Mall and the terminus of Interstate 405. The interchange lacks connections to the north side of I-5, which are provided by the parallel Interurban Avenue, and has a direct offramp to the high-occupancy vehicle lanes on southbound I-5.<ref>{{cite web |date=February 28, 2017 |title=SR 5 – Exit 156: Junction SR 599/Interurban Avenue |url=http://www.wsdot.wa.gov/mapsdata/tools/InterchangeViewer/pdf/SR005/005X156.pdf |publisher=Washington State Department of Transportation |access-date=December 23, 2018}}</ref> The only intermediate junction on SR&nbsp;599 is a partial cloverleaf interchange at South 133rd Street near several office parks, including the headquarters of BECU.<ref name="google">{{google maps |title=State Route 599 |url=https://www.google.com/maps/dir/47.4828005,-122.2713875/47.4982494,-122.2948193/@47.4903761,-122.2918874,15z/am=t/data=!3m1!4b1!4m2!4m1!3e0 |access-date=December 23, 2018}}</ref><ref name="Junction">{{cite web |date=June 15, 2015 |title=SR 599: Junction Interurban Avenue/S 133rd Street |url=http://www.wsdot.wa.gov/mapsdata/tools/InterchangeViewer/pdf/SR599/599X000.pdf |publisher=Washington State Department of Transportation |access-date=December 23, 2018}}</ref>

The freeway then travels northwest, following the elevated Central Link light rail tracks to the west and the Duwamish River and the Green River Trail to the east.<ref>{{cite map |title=Link light rail |url=http://www.soundtransit.org/schedules/light-rail/link-light-rail/map |publisher=Sound Transit |cartography=Bing Maps |access-date=August 22, 2016}}</ref> SR&nbsp;599 then turns west to travel around a King County Metro bus base, which has a direct onramp to the southbound freeway,<ref name="Junction"/> and crosses under the light rail tracks at East Marginal Way South. The freeway turns west and intersects Tukwila International Boulevard, which marks the end of SR&nbsp;599 and where SR&nbsp;99 resumes.<ref>{{cite web |date=January 21, 2010 |title=SR 99: Junction SR 599/Tukwila International Boulevard |url=http://www.wsdot.wa.gov/mapsdata/tools/InterchangeViewer/pdf/SR099/099X022.pdf |publisher=Washington State Department of Transportation |access-date=December 23, 2018}}</ref> SR&nbsp;99 continues northwest along the freeway and into Seattle on West Marginal Way.<ref name="google"/>

SR&nbsp;599 is maintained by the Washington State Department of Transportation (WSDOT) and is designated as a minor route of the National Highway System.<ref>{{cite web |title=2017 State Highway National Highway System Routes in Washington |url=https://www.wsdot.wa.gov/mapsdata/travel/hpms/pdf/washington-2017-state-highway-nhs-list.pdf |publisher=Washington State Department of Transportation |access-date=December 23, 2018}}</ref> WSDOT conducts an annual survey of average traffic volume on the state highway system that is measured in terms of annual average daily traffic, finding in 2016 that approximately 44,000&nbsp;vehicles use SR&nbsp;599.<ref>{{cite report |year=2017 |title=2016 Annual Traffic Report |page=213 |url=https://www.wsdot.wa.gov/mapsdata/travel/pdf/Annual_Traffic_Report_2016.pdf |publisher=Washington State Department of Transportation |url-status=dead |archive-url=https://web.archive.org/web/20200208001700/https://www.wsdot.wa.gov/mapsdata/travel/pdf/Annual_Traffic_Report_2016.pdf |archive-date=February 8, 2020 |access-date=December 23, 2018}}</ref>

==History== SR&nbsp;599 became a state highway in 1971,<ref name="rcw">{{cite web |url=http://apps.leg.wa.gov/RCW/default.aspx?cite=47.17.808 |title=RCW 47.17.808: State Route 599 |author=Washington State Legislature |author-link=Washington State Legislature |access-date=September 28, 2008}}</ref> but had been part of Washington's older highway system (Primary and Secondary Highways) from 1957 to 1970.<ref name="1957-law">{{cite book |author-link=Washington State Legislature |author=Washington State Legislature |title=Session Laws of the State of Washington |url=https://books.google.com/books?id=Zck4AAAAIAAJ |access-date=August 10, 2008 |edition=1957 |year=1957 |publisher=Washington State Legislature |location=Olympia, Washington |chapter=Chapter 172}}</ref> The highway, then known as PSH 1 WM, or West Marginal Branch,<ref name="1957-law"/> was built during the 1960s. When it was completed and opened to traffic in June 1968,<ref>{{Cite web|url=https://cdm16977.contentdm.oclc.org/digital/collection/p16977coll3/id/369/rec/13|title = SR 99 I-5 to Pacific Highway South Opening June 25, 1968 4}}</ref> U.S. Route&nbsp;99 (US&nbsp;99) was about to be removed from the system, so when I-5 was completed up to Tukwila, US 99 switched to the route of SR&nbsp;599. Later on, the current route of SR&nbsp;599 became known as US&nbsp;99T (Temporary) and later SR&nbsp;99T in 1964. In 1971, the highway became SR&nbsp;599.<ref name="rcw"/> SR&nbsp;181 was temporarily routed alongside the freeway on Interurban Avenue until 1971.<ref>{{Cite web|url=https://www.flickr.com/photos/tigerzombie/5069068935/sizes/o/|title = All sizes &#124; Seattle Street Map 1966 Chevron &#124; Flickr - Photo Sharing!}}</ref>

==Exit list== {{jcttop|state=WA|county=King|location=Tukwila|length_ref=<ref name="log"/>}} {{WAint |mile=0.00 |type=incomplete |road={{jct|state=WA|I|5|to2=to|I|405|location1=Portland}} |notes=Southbound exit and northbound entrance }} {{WAint |mile=0.36 |road=South 133rd Street / Interurban Avenue &nbsp;– Tukwila |notes= }} {{WAint |mile=0.83 |type=incomplete |road=King County Metro South Base |notes=Southbound entrance only }} {{WAint |mile=1.75 |road={{jct|state=WA|SR|99|dir1=north|road|Tukwila International Boulevard|city1=Seattle}} |notes=Continues north as SR&nbsp;99 }} {{jctbtm|keys=incomplete}}

==References== {{Reflist|33em}}

==External links== {{Attached KML}} {{commons category}} *[https://www.angelfire.com/wa2/hwysofwastate/sr599.html Highways of Washington State] *[http://www.wsdot.wa.gov/Traffic/seattle/direction/I5_SR599_interchange.htm Traffic camera for SR&nbsp;599 {{spaced ndash}} I-5 Interchange (WSDOT)]

{{State highways in Washington related to I-5}}

599 Category:U.S. Route 99 Category:Freeways in the United States Category:Transportation in King County, Washington