U.S. Route 99 (US 99) was a main north–south United States Numbered Highway on the West Coast of the United States until 1964, running from Calexico, California, on the US–Mexico border to Blaine, Washington, on the U.S.-Canada border. It was assigned in 1926 and existed until it was replaced for the most part by Interstate 5. Known also as the "Golden State Highway" and "The Main Street of California", US 99 was important throughout much of the 1930s as a route for Dust Bowl immigrant farm workers to traverse the state. Large portions are now California's State Route 99 (SR 99), Oregon Route 99, 99W, 99E and Washington's SR 99. The highway in Washington connected to British Columbia Highway 99 at the Canada–US border.