The soaring spire of Mount Thielsen is the highest of several eroded volcanic remnants which mark the central part of the Cascade Range in Orgeon. Several hundred thousand years ago, Thielsen was a broad shield volcano much like its western neighbor across Diamond Lake, Mount Bailey. Several stages of heavy glaciation have stripped away the outer cone, leaving behind only the hard remnants of solidified magma which mark the inner conduits, and broad talus slopes between the ridges. The summit spire itself requires one pitch of roped class-5 climbing and is unskiable in any conditions. Thielsen also hosts Oregon's most southerly glacier, the tiny Lathrop Glacier, but it is located high on the craggy north face and is not a good ski objective. The steep talus slopes, especially the Southwest Face, provide excellent ski terrain when snow-covered in winter and spring, although they do not retain snow long into summer.

Click on any photo to go there, or start your tour with the first photo...

Trip Summary: Tuesday, June 22, 1999

This was a private trip, with a party of two (myself and Alex Cronin).
I skied on randonnee (alpine touring) gear, Alex skied on heavy-duty telemark gear.