Lookout Mountain is a 5,699-foot summit in Washington’s North Cascades, near Marblemount, known especially for the historic U.S. Forest Service lookout on its peak. The current lookout, built in 1962 to replace a 1929 structure, stands atop a mountain reached by a steep trail climbing more than 4,400 feet. Its summit offers broad views across surrounding peaks and ridges. The mountain lies in a marine west coast climate that brings heavy rain, winter snow, and avalanche danger, with clearer summers. Its rugged setting was shaped over millions of years by tectonic uplift, volcanic activity, terrane accretion, and repeated Pleistocene glaciation.