I also shot all of the volcanoes – had to adjust for the airplane window in photoshop though. Crater Lake was once a giant volcano named Mount Mazama and reached 11,000 feet! Then it blew up :) Wikipedia has some good information on the formation of the lake here. Apparently crater lakes are a geological feature with the subject of this post being one of the most well known in the US. There are other crater lakes in North America and around the world.