Located in the high desert at the base of the Eastern Sierras near Lee Vining, California, Mono Lake is one of the oldest lakes in the western hemisphere, estimated to be over a million years old. The massive lake covers about 60 square miles of the Mono Basin and is mostly known for its distinct tufa (calcium carbonate) formations. The lake has no outlet, making it incredibly salty. This allows swimmers to float like a cork on the water. Mono Lake is also an exceptional place for bird watching, as migratory birds stop over to rest and feed on the abundance of brine shrimp that thrive in the salty water.