Foss Peak

Foss Peak is a summit in the Tatoosh Range located south of Mount Rainier within the national park boundaries. The peak sits at approximately 6,500 feet and connects to other peaks in this mountain chain that draw climbers and hikers throughout the year.

The summit was named after Thea Foss, a businesswoman who was active in Washington state during the early 1900s. The peak has been a recognized climbing destination in this mountain range for many decades.

The peak forms part of several mountaineering challenges, including the Mount Rainier 100 Peaks Pin program organized by the Mountaineers Club.

The best time to climb is from June through September when snow coverage is minimal and conditions are safest. Routes require proper gear and fitness levels, so visitors should prepare accordingly before attempting the ascent.

The peak is also known locally by the name Manatee Mountain, an alternative designation rarely used in climbing communities. Water draining from the summit flows into tributaries that feed the Cowlitz River system.

GPS coordinates: 46.75522,-121.71271

Latest update: December 14, 2025 20:01