Mosier Twin Tunnels

  • Easy (from east trailhead)
  • 1.8 miles round trip
  • 160 feet elevation gain
  • Open all year
  • Use: hikers, horses, bicycles


  • Moderate (entire trail)
  • 9.4 miles round trip
  • 960 feet elevation gain

Tunnels with gracefully arched rock windows pierce the basalt cliffs high above the Columbia River at Mosier. The twin tunnels were built in 1919-21 for the historic Columbia River Highway, one of America’s earliest and most beautiful pleasure drives. When falling rocks from the cliffs above damaged several cars in 1953, engineers backfilled the tunnels and rerouted traffic onto a new, river-level route—now Interstate 84.

Still, many people remained nostalgic for the old highway, with its daring tunnels, grand panoramas, graceful curves, delicate bridges, and stonework railings. And so in 1995, workers began reopening portions of the original route as the Historic Columbia River Highway State Trail. Much of this paved path is best toured by bicycle, but the twin tunnels near Mosier are interesting enough to attract hikers as well.

To start, drive …

This chapter taken from the book 100 Hikes/Travel Guide: Northwest Oregon & Southwest Washington.