Camp Muir, named for the naturalist John Muir, is a high-altitude refuge for climbers on Mount Rainier in Mount Rainier National Park The shelters comprising the camp are situated at a elevation between the Muir Snowfield and the Cowlitz Glacier on Mt. Rainier. Camp Muir is the most-used base camp for those attempting to climb to the mountain's summit. Camp Muir is between the Nisqually and Paradise Glaciers. The larger "public" shelter hut was built in 1921 to plans supervised by Daniel Ray Hull of the National Park Service. The by single-story one-room shelter was initially constructed of dry-laid stone. It replaced a smaller shelter which was used as a shelter for climbing guides. A dedication plaque at the entrance to the large shelter plaque reads "Erected in memory of John Muir, 1921." The guide shelter was built in 1916 by a climbing organization, the Mountaineers. It was designed by Seattle architect Carl F. Gould, a member of the Mountaineers and was approved by Park Service director Stephen T. Mather. The single-story guide shelter measures about by , and is the oldest stone structure in the park. Two stone pit toilets were built at Camp Muir in 1936 by the Civilian Conservation Corps, one of which survives and is used for storage.