Lake Mead National Recreation Area
Annual visitors: 7.3 million
Location: Temple Bar Marina, Ariz.
Size: 2,337 square miles
Founded: 1936
Highlights: It may be in the middle of the desert, but lakes Mead and Mohave offer plenty of chances for water sports like fishing, kayaking, and canoeing. Beyond the water, hikers will find thousands of desert wildlife.
