Crater Lake and Wizard Island, Oregon.

Crater Lake formed by the catastrophic eruption of Mt. Mazama, a medium-sized stratovolcano of the Oregon Cascades, about 6850 years ago. During this eruption, so much material was emptied from the underlying magma chamber that much of the volcano collapse downward, forming the caldera, which later filled in with water. Wizard Island formed as a series of andesitic eruptions soon after the caldera collapse. Crater Lake is now the deepest lake in the United States, with at depth of 1949 feet.

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