Iron Horse / Palouse to Cascades Trail

The Iron Horse Trail (renamed Palouse to Cascades State Park Trail in 2018) follows the abandoned Milwaukee Road right-of-way 285 miles across Washington — from the Idaho border to the Cedar Falls trailhead just outside Seattle. The trail's signature feature is the Snoqualmie Tunnel, a 2.3-mile straight bore under Snoqualmie Pass that requires a headlamp and stays at 50 degrees year-round; the tunnel is closed November through April annually due to ice danger. The rail-grade never exceeds 2 percent, which means cyclists can ride 50-mile days without significant climbing despite crossing the entire state. Lake Easton State Park (32-ft cap, electric, on the western Cascade slope) is the highest-quality rig basecamp for the tunnel approach. The trail east of Cle Elum runs through high-desert ranch country where summer temperatures push 100°F and water sources sit 30+ miles apart — bring more water than you think you need.