Mount Thielsen

Mt. Thielsen

  • Difficult (to Pacific Crest Trail)
  • 7.6 miles round-trip
  • 1950 feet elevation gain
  • Open end of July through October

  • Very Difficult (to summit)
  • 10 miles round-trip
  • 3800 feet elevation gain

Towering above Diamond Lake, Mt. Thielsen’s stony spire commands views from Mt. Shasta to the Three Sisters. A popular path climbs to the Pacific Crest Trail on Mt. Thielsen’s flank. Hardy hikers can continue to a dizzying ledge at the base of the summit spire, and many dare to scale the final pitch as well.

Originally a broad, 11,000-foot volcano, Mt. Thielsen stopped erupting about 100,000 years ago when a lava plug blocked its throat. Since then, erosion by Ice Age glaciers has left this hard lava core exposed as the summit spire. The peak’s nickname, “Lightning Rod of the Cascades,” reflects both its shape and its weather. Lightning has left the summit boulders spattered with black fulgurite—glassy recrystalized rock. The name Thielsen (pronounced TEEL-sun) honors a Danish-American pioneer railroad engineer.

To drive here from …

This chapter taken from the book 100 Hikes in Southern Oregon.