National park, northwestern Washington, U.S. Established in 1968 to preserve mountain snowfields, glaciers, alpine meadows, and lakes in the northern part of the Cascade Range , it covers an area of 504,781 acres (204,278 hectares).
The Ross Lake National Recreation Area separates the park into two sections, the northern unit extending to the Canadian border and the southern unit adjoining the Lake Chelan National Recreation Area.