U.S. Route 101
U.S. Route 101, or U.S. Highway 101 (US 101) is a north–south United States Numbered Highway that runs through the states of California, Oregon, and Washington, on the West Coast of the United States. It is also known as (The Royal Road) where its route along the southern and central California coast approximates the old trail which linked the Spanish missions, pueblos, and presidios. It merges at some points with California State Route 1 (SR 1).
U.S. Route 101 in Washington
U.S. Route 101 Alternate is a 0.61-mile (0.98 km) bypass of Ilwaco. US 101 Alt. opened in 1931 as a branch of PSH 12, the early designation of the southern section of US 101 through Washington. The highway was not fully recognized by the AASHTO until October 2006, even though many maps from the 1930s state that it is part of the U.S. Route system.