The lake is 1,943 feet deep at its deepest point, which makes it the deepest lake in the United States, the second deepest in North America and the ninth deepest in the world. Crater Lake is often referred to as the seventh deepest lake in the world. However, when comparing its average depth of 1,148 feet 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 deep caldera formed 7,700 years ago during the violent climactic eruptions and subsequent collapse of Mount Mazama and the relatively moist climate that is typical of the crest of the Cascade Range.
The caldera rim ranges in elevation from 7,000 to 8,000 feet). The United States Geological Survey bench marked elevation of the lake surface itself is 6,178 feet (1,883 m). This National Park encompasses 183,224 acres (286.29 sq mi; 74,148.12 ha; 741.48 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 re-filled entirely from direct precipitation in the form of snow and rain.