Washington State Route 900 State Route 900 is a state highway in the state of Washington , USA , getting its number as the westernmost spur of Interstate 90 . It extends 16.20 miles ( 26.07 km ) from I-5 in Tukwila east to I-90 in Issaquah . Route description SR 900 begins at the intersection with Ryan Way at I-5 exit 157 , near the southeast corner of Boeing Field . It heads south on Martin Luther King Jr . Way ( formerly Empire Way ) , with ramps to and from I-5 , before splitting from the alignment of I-5 and heading east into Renton ( with a short section in Seattle ) . It heads into downtown Renton on Sunset Boulevard . At State Route 167 , a one-way pair begins , with eastbound SR 900 on Third Street and westbound SR 900 on Second Street . At State Route 515 , SR 900 heads northeast on Houser Way ( eastbound ) and Bronson Way ( westbound ) , and after a block SR 900 east turns north on Mill Avenue to rejoin the westbound side on Bronson Way . Just before Bronson Way crosses under I-405 , SR 900 turns north along the west-side frontage road , Sunset Boulevard . Sunset crosses to the east side of I-405 and then turns east , taking SR 900 between the slopes of Cougar Mountain and Squak Mountain to its end at I-90 in Issaquah ( though the name changes to Renton-Issaquah Road ) . Lake Sammamish State Park lies right across I-90 from the end of SR 900 . History Before April 1 , 1992 , SR 900 continued west ( compass north ) along Martin Luther King , Jr . Way and Rainier Avenue to end at I-90 exit 3 . The west end of SR 900 is now milepost 5.93 due to this truncation ; the east end is milepost 21.64 . Before the Lake Washington Floating Bridge was built across Lake Washington in 1940 , SR 900 was one of the major roads east from Seattle , taking US 10 and Primary State Highway 2 around the south side of the lake . It had been established by the legislature as a State Highway in 1909 , and PSH 2 was completed for through traffic in 1915 ( the last section being east of SR 900 , through Snoqualmie Pass ) . The opening of the bridge in 1940 moved US 10/PSH 2 to the direct route , and the old alignment became Alternate US 10 and PSH 2 RE ( for Renton ) . In 1955 , Alternate US 10 was dropped , and it became SR 900 in 1964 . See also List of Washington State Routes External links Highways of Washington State - SR 900 Highways of Washington State - Primary State Highway 2-Sunset Highway Highways of Washington State - State Road No. 2 Sunset Highway RCW 47.17.825 : Legal definition of SR 900 edit State routes in Washington related to I-90 SR 900 - SR 902 - SR 903 ( Spur ) - SR 904 - SR 906 ( Spur ) - SR 908 Former or proposed state routes : SR 901 - SR 920 This article relating to Washington State Routes is a stub . Please support the Washington Highway WikiProject and help Wikipedia by expanding it . Categories : King County , Washington | Washington state highways | Washington state highway stubs Interstate 90 