Pacific Highway (United States) from the Hudson's Bay Company were the first non-Native Americans to use the route of the future Pacific Highway to move between today's Washington State and "Alta California." During the second half of the 19th Century, mule trains, stagecoaches, and the Central Pacific Railroad also followed the route of the Siskiyou Trail. In the early 20th century, around 1910, entrepreneur Sam Hill lobbied the governments of Washington and Oregon to build automobile roads along the path of the Siskiyou Trail, with the ultimate goal of building a paved auto route from Canada to Mexico. Pacific Highway (United States) Pacific Highway
Washington State Route 547 defunct Sumas–Glacier route of the Chicago, Milwaukee, St. Paul and Pacific Railroad. In 1984, the Washington State Legislature and Washington State Department of Transportation added the road to the state highway system. Washington State Route 547 State Route 547 (SR 547) is a Washington state highway located in Whatcom County, south of the Canada–US border. The long route runs northwest from in Kendall to in Sumas. The highway was originally created in 1984, but a road extending from Kendall to Sumas has been on maps since 1966 along the Sumas–Glacier route of the Chicago, Milwaukee, St. Paul and Pacific Railroad.