Pinnacle Peak is a 7,386-foot summit in Washington’s North Cascades National Park, rising steeply above Diablo Lake between Pyramid Peak and Paul Bunyans Stump. More notable for its dramatic local relief than for great absolute height, it forms part of a ridge system extending south toward prominent climbing peaks. Its rugged setting reflects millions of years of tectonic activity, uplift, faulting, terrane accretion, and later Pleistocene glaciation, which carved the surrounding U-shaped valleys and steep slopes. In the marine west coast climate zone, the mountain receives heavy precipitation and wet winter snow that can create dangerous avalanche conditions, while its runoff drains to Diablo Lake and the Skagit River.