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.
Arizona State Route 101
Arizona State Route 101, or Loop 101, (spoken as one-oh-one) is a semi-beltway encompassing much of the Phoenix Metropolitan Area in the United States. It connects several suburbs of Phoenix, including Tolleson, Glendale, Peoria, Scottsdale, Mesa, Tempe, and Chandler. Construction began in the late-1980s and was completed in 2001.
Additional general purpose lanes and a high occupancy vehicle lane (HOV) are being constructed along the eastern stretch of Loop 101 from Scottsdale to Chandler, starting at Princess Drive to Loop 202 (the Santan Freeway).