Tenpeak Mountain is an granitic mountain summit located in the Glacier Peak Wilderness of the North Cascades in Washington state. Fred Beckey's Cascade Alpine Guide has the elevation of the mountain as 8,281 feet. Tenpeak is situated on the crest of the Cascade Range, on the shared border of Snohomish County and Chelan County, also straddling the boundary between the Mount Baker-Snoqualmie National Forest and the Wenatchee National Forest. Its nearest higher neighbor is Luahna Peak, to the southeast. Topographic relief is significant since the northern aspect of the mountain rises 4,200 feet above the Suiattle Valley in approximately . This mountain has small, unnamed, hanging glaciers in cirques surrounding the summit, and the terminus of the Honeycomb Glacier lies below the western base of the mountain. Precipitation runoff from the mountain and meltwater from the glaciers drains south into White River; or north into the Suiattle River. This mountain's descriptive name was suggested by The Mountaineers, and was officially adopted in 1918 by the U.S. Board on Geographic Names. The first ascent was made September 21, 1940, by Lloyd Anderson and Tom Campbell.