Interstate 405 (I-405) - North-South Bypass of Seattle

Known in Washington state simply as the 4-0-5, Interstate 405 is a 30 mile highway that travels east of Lake Washington and circumvents Seattle to the east.  It is the most congested highway in the state. The most heavily trafficked portion of the highway is  SE 85th Street near downtown Bellevue with approximately 200,000 cars traveling daily.

I-405 runs through the "Eastside" technology coordinator of Bellevue and Kirkland. It connects with major state routes, Interstate 90 and Interstate 5.

The highway goes through two counties: King and Snohomish. On the South end of the freeway is in Tukwila while the northernmost terminus is in Lynnwood.

The Washington State Department of Transportation has a master plan for I-405 improvements to enable traffic of 800,000 daily to run smoothly. The master plan includes creating vanpools, increasing transit service and adding more park-and-ride spaces along the freeway. Click here for more information.

Interstate 405 (I-405) - North-South Bypass of Seattle