Crater Lake is a caldera lake in the western United States, located in south-central Oregon. It is the main feature of Crater Lake National Park and is famous for its deep blue color and water clarity. The lake partly fills a nearly 2,148-foot (655 m)-deep caldera that was formed around 7,700 (± 150) years agoby the collapse of the volcano Mount Mazama. Human interaction is traceable back to the indigenous Native Americans witnessing the eruption of Mount Mazama. There are no rivers flowing into or out of the lake; the evaporation is compensated for by rain and snowfall at a rate such that the total amount of water is replaced every 250 years. At 1,943 feet (592 m), the lake is the deepest in the United States, and the seventh or ninth deepest in the world, depending on whether average or maximum depth is measured.

http://en.wikipedia.org/wiki/Crater_Lake

This pano was made during a landscape photography workshop with Marc Adamus