Iron Horse State Park, Rail trail in Cascade Mountains, Washington

Iron Horse State Park is a 1,612-acre state park in the Cascade Mountains and Yakima River Valley, between Cedar Falls and the Columbia River. It contains most of the developed sections of the Palouse to Cascades State Park Trail, a rail trail of 300 miles (480 km) that follows the former Milwaukee Road roadbed from the western slopes of the Cascades to the Idaho border. The trail crosses Snoqualmie Pass through the 2.3-mile Snoqualmie Tunnel.

The trail follows the former Chicago, Milwaukee, St. Paul & Pacific Railroad line that was abandoned in 1980. Following the closure, the railroad infrastructure was converted into a recreation trail open to the public.

The path takes its name from the John Wayne Pioneer Wagons and Riders Association, which organized annual horse and wagon journeys across the state. Today, hikers and cyclists use the route as a passage through remote mountain communities.

Several access points allow entry to different sections, and many have basic facilities at trailheads. For the Snoqualmie Tunnel passage, bring a powerful flashlight since the tunnel is quite dark.

The Snoqualmie Tunnel, part of this trail, is 11,894 feet (3,625 m) long and was tunnel #50 on the Milwaukee Road. It is not the world's longest railroad tunnel. The trail also has five other tunnels: Boylston (#45), Thorp (#46), Picnic Area (#47), Easton (#48) and Whittier (#49).