U.S. Route 101
The nearly highway's northern terminus is in Tumwater, Washington: the route remains along the Olympic Peninsula's coastal perimeter west, north, and east; the northernmost point on the highway is in Port Angeles. The southern terminus of US 101 is in Los Angeles at the East Los Angeles Interchange, the world's busiest freeway interchange.
Santa Maria, California
U.S. Route 101 runs through the middle of the Santa Maria Valley and is the main freeway connecting many west coast cities. It has been improved to freeway status (meaning all at-grade intersections have been eliminated) within the city of Santa Maria itself. There was recently a widening project that expanded the freeway from four to six lanes between Santa Maria Way and the highway 166 exit. The $32 million project was completed in late 2008 / early 2009.