2. Lake Powell, Utah and ArizonaThough this lake is not a naturally made lake but of human creation, it is a truly beautiful location. The lake was created when Glen Canyon was damned up, causing the Colorado River to rise and make the second largest reservoir in the U.S.
However, once that process was completed, the glory of Lake Powell was revealed. There are red sandstone cliffs (including the Rainbow Bridge), canyons, and warm waters that come together for a mind-blowing experience.