rainier

Rainier, officially Mount Rainier, is an active stratovolcano in the Cascade Range of the Pacific Northwest, United States. It is the highest peak in Washington state and the entire Cascade Range, rising to 14,411 feet (4,392 meters). The mountain stands southeast of Seattle in Pierce County and serves as the centerpiece of Mount Rainier National Park, established in 1899.

Geology and glaciology: Rainier is part of the Cascade Volcanic Arc, formed by subduction of the Juan de Fuca Plate beneath the North American Plate. It is heavily glaciated, with dozens of glaciers that drain the summit area, including the Emmons Glacier and the Nisqually Glacier. Meltwater from the glaciers feeds rivers such as the Nisqually and Puyallup, shaping the surrounding landscape and contributing to regional hydrology.

Hazards and climate: As an active volcano with a large snow and ice cover, Rainier poses potential hazards to nearby communities, including lahars, landslides, and ash fall during eruptions. The mountain and surrounding park are monitored by the U.S. Geological Survey and other agencies. The climate is alpine, characterized by heavy snowfall, rapidly changing weather, and strong wind in the summit region. Glacial retreat has been observed in recent decades, affecting runoff and habitats.

Name and history: The name Rainier derives from Captain Peter Rainier of the Royal Navy; the mountain was named by explorer George Vancouver in the late 18th century. In United States usage the peak is officially Mount Rainier, though the name Rainier remains common. The mountain is a major destination for sightseeing and mountaineering, with established routes such as the Disappointment Cleaver for experienced climbers.