Palouse to Cascades State Park Trail, National Recreation Trail in Washington, United States.

The Palouse to Cascades State Park Trail is a former railroad line that stretches across Washington state from the Idaho border to the Cascade Mountains. The route passes through forests, farmland, and mountain terrain, offering different landscapes for hikers and cyclists.

The route was once part of the Chicago-Milwaukee-St. Paul-Pacific Railroad system and served as a major transportation corridor until 1980. After the railroad was decommissioned, the corridor was transformed into a public recreation trail for everyone to use.

The trail's name comes from the Palouse region and the Cascade Range it crosses. The eastern section was called the John Wayne Trail after the John Wayne Pioneer Wagons and Riders Association, founded by Chic Hollenbeck, which from 1981 held annual horse and wagon rides along the route to keep the land in public hands. The western 100 miles were the Iron Horse Trail.

The trail is accessible year-round, though hikers and cyclists should wear sturdy footwear or use appropriate tires since the surface varies. In winter, certain sections can become slippery, so caution is needed and proper gear makes the visit more enjoyable.

The Snoqualmie Tunnel, numbered 50 by the Milwaukee Road, runs 11,894 feet (3,625 m) beneath the crest of the Cascades at Hyak; the other five are Boylston (#45), Thorp (#46), Picnic Area (#47), Easton (#48) and Whittier (#49). The Boylston Tunnel was also called Johnson Creek by the railroad, and #46 and #47 are sometimes grouped as the Thorp Tunnels.