Crater Lake National Park is an American national park located in southern Oregon. Established in 1902, Crater Lake is the fifth-oldest national park in the United States and the only national park in Oregon. The park encompasses the caldera of Crater Lake, a remnant of Mount Mazama, a destroyed volcano, and the surrounding hills and forests. The caldera rim ranges in elevation from 7,000 to 8,000 feet (2,100 to 2,400 m). The United States Geological Survey benchmark elevation of the lake surface is 6,178 feet (1,883 m). The national park encompasses 183,224 acres (286.3 sq mi; 741.5 km2). Crater Lake has no streams flowing into or out of it. All water that enters the lake is eventually lost from evaporation or subsurface seepage. The lake's water commonly has a striking blue hue, and the lake is refilled entirely from direct precipitation in the form of snow and rain.