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.
Special routes of U.S. Route 101
A total of fifteen special routes of U.S. Route 101 exist.
Present SR 1 in the Los Angeles area was U.S. Route 101 Alternate from the mid-1930s to 1964.
The precursor to the Santa Ana Freeway between Los Angeles and Anaheim was U.S. Route 101 Bypass from the early 1940s to the mid-1950s, when it became part of US 101. Old US 101 there is now partially SR 72.