Lost Peak is an 8,464-foot mountain in the Okanogan Range of north-central Washington, within the remote Pasayten Wilderness of the Okanogan–Wenatchee National Forest. About 16 miles north of Mazama, it is counted among Washington’s major summits, ranking 62nd on the state’s highest 100 peaks and 63rd on the Bulger List. Runoff from the mountain enters tributaries of the Lost River and then the Methow River basin. The peak also reflects the larger North Cascades landscape, formed through tectonic assembly and terrane accretion, then deeply sculpted by repeated Pleistocene glaciations that created the region’s sharp ridges and deep valleys.