Crater Lake National Park is a United States National Park located in Southern Oregon whose primary feature is Crater Lake. It was established on May 22, 1902, as the sixth National Park in the U.S. The park encompasses Crater Lake's caldera, which rests in the remains of a destroyed volcano posthumously called Mount Mazama. It is the only National Park in Oregon.
The lake is 1,949 feet (594 m) deep at its deepest point which makes it the deepest lake in the United States, second in North America, and according to Wikipedia's list of lakes by depth, the ninth deepest anywhere in the world.[note 1] However, when comparing its average depth of 1,148 feet (350 m) to the average depth of other deep lakes, Crater Lake becomes the deepest in the Western Hemisphere and the third deepest in the world. The impressive average depth of this volcanic lake is due to the nearly symmetrical 4,000-foot (1,200 m) deep caldera formed 7,700 years ago during the violent climactic eruptions and subsequent collapse of Mt. Mazama and the relatively moist climate that is typical of the crest of the Cascade Mountains.
The caldera rim ranges in elevation from 7,000 to 8,000 feet (2,100 to 2,400 m). The USGS benchmarked elevation of the lake surface itself is 6,178 feet (1,883 m). The park covers 286 square miles (741 km2). Crater Lake has no streams flowing into or out of it. The lake's water regularly has a striking blue hue and is filled entirely from direct precipitation in the form of snow and rain. All water that enters the lake is eventually lost from evaporation or subsurface seepage.