Stevens Pass is named for John F. Stevens, an engineer in the employ of the Great Northern Railway. He had located the route the railway took over the Rockies, Marias Pass, and he had found the route over his eponymous pass. Not an ideal route but workable and James Jerome Hill had little time to waste.

There were three different attempts to establish an acceptable route over the Cascades. The first route, the path Mark Twain and company traveled in 1895 required eight switchbacks, sharp curves, steep grades up to four percent, and a crew of 3,000 men working 12 hours a day for two years to complete. The final spike was driven on January 6, 1893. Mark Twain traveled this route August 8, 1895 riding the Great Northern Railway from Spokane to Seattle. He rode on the engine with the engineer, who was delighted.

Soon after the Great Northern reached Seattle, much of America suffered the Panic of 1893. It was devastating to many established businesses but proved a boon to the new businesses along the line. JJ Hill had been very busy extending the advice of Horace Greeley, continue on west. This helped provide a renewed supply of labor to develop, among other places, Skykomish Valley, just west of the switchbacks.

Earlier transcontinental railroads had employed cheap Chinese labor, upsetting unemployed whites, resulting in the Chinese Exclusion Act of 1881, a federal law barring Chinese from entering the United States to work on railroads. Hill had been negotiating with the Japanese, he wished to sell them U.S. goods and import silk and tea. It is also possible that he was able to procure cheap Japanese labor, although this is not documented. The 1900 census mentions 47 Japanese workers in Wellington and Martin Creek but it does not mention the town of Nippon.

Whether a town was located for mining or for the railroad, they all had sawmills. There was a definite local market for lumber but JJ Hill knew there was a much bigger market in the east. Hill knew he could only make money if he could fill his freight cars in both directions. In addition to products from the Orient, he recognized the the Great Northern could transport lumber east on cars that would otherwise travel empty. He convinced his friend and neighbor Frederick Weyerhaeuser to look to the west with him.

Even after construction, the railroad remained labor intensive. The large crews needed to build the line became large maintenance and snow removal crews. The route over Stevens Pass was hardly ideal, with eight switchbacks and sections of track above 3,000 feet in a serious snow belt. Snaking railcars in eight-car units up and down the switchbacks required crews working around the clock.

Work began on the first Cascade Tunnel in 1897 and was completed in 1900. It relieved the railroad of the switchbacks but brought its own set of problems, particularly the exhaust from the steam engines causing several deaths in the tunnel and numerous close calls. By 1909 the tunnel had become electrified and electric engines pulled the trains through the tunnel. But the line was still in dangerous snow country.

In March 1910, the most disastrous avalanche in U.S. history occurred at Wellington. Ninety six people died when an avalanche crashed into a stalled train. In 1929 the Great Northern Railway completed the construction of the second Cascade Tunnel, 7.8 miles long and still in operation. This tunnel had disastrous effects on the town of Leavenworth, bypassed by the new route.