Crater Lake and Wizard Island, in Cater Lake National Park, Oregon. The lake is the deepest in North America, having formed after the massive eruption and subsequent collapse of Mount Mazama, about 7600 years ago. Wizard island is a lava dome that subsequently formed inside the crater. There are no known river flows in or out of the lake, so it is fed by rainwater and drained through evaporation. The deep blue colour is a result of the lake's extreme depth.

Crater Lake National ParkOregon Vacation 2009