The Chicago, Milwaukee, St. Paul and Pacific Railroad (Milwaukee Road) formerly ran along the west shore of the lake and crossed the Cascades through the 2¼-mile (3.6 km) Snoqualmie Tunnel, with its east portal at Hyak. Late to the West with its Pacific Extension, the Milwaukee Road's traffic to Tacoma began in 1909 and initially was routed over Snoqualmie Pass; the tunnel opened five years later in 1914 and heads due west from Hyak at an approximate elevation of . Close to the east portal near the lake's northwest shore was the Milwaukee Ski Bowl, built in 1937 and operated by the railroad until 1950.