U.S. Route 101 in Washington - History

History

Before U.S. Route 101 was created, two roads existed in the place of US 101. They were State Road 9 and State Road 12. These were two roads that were part of the early Washington State Road system that was created in 1923. US 101 was created in 1926 and was co-signed with these two routes. US 101 took part of State Road 9's route and part of State Road 12's route.

In 1937, the Washington State Legislature established a new system, the Primary and secondary system. State Road 9 became Primary State Highway 9 or PSH 9. State Road 12 became PSH 12, and they both held the co-signed designation with US 101.

There was nothing changed about US 101's route from 1937 to 1956. In 1956, President Dwight D. Eisenhower signed the Interstate Highway Act into law. This eliminated part of the U.S. Route system and encouraged Washington's Legislature to once again change the highway system.

In January 1964, the Washington State Legislature and the Washington Department of Highways (renamed WSDOT) approved a new state route system with no branches or secondary route with names, but a full system that lives on today. PSH 9 and PSH 12 became part of U.S. Route 101 with no co-designation and parts of them became other new state routes.