Olympic National Park Washington
Glaciated mountains
Within the center of Olympic National Park rise the Olympic Mountains whose sides and ridgelines are topped with massive, ancient glaciers. The mountains themselves are products of accretionary wedge uplifting related to the Juan De Fuca Plate subduction zone. The geologic composition is a curious mélange of basaltic and oceanic sedimentary rock. The western half of the range is dominated by the peak of Mount Olympus, which rises to 7,965 feet (2,428 m). Mount Olympus receives a large amount of snow and consequently has the greatest glaciation of any non-volcanic peak in the contiguous United States outside of the North Cascades. It has several glaciers, the largest of which is Hoh Glacier at 3.06 miles (4.93 km) in length. Looking to the east, the range becomes much drier due to the rain shadow of the western mountains. Here, there are numerous high peaks and craggy ridges. The tallest summit of this area is Mount Deception, at 7,788 feet (2,374 m).