Mono Lake is a majestic body of water covering about 65 square miles. It is an ancient lake, over 1 million years old -- one of the oldest lakes in North America. It has no outlet. Throughout its long existence, salts and minerals have washed into the lake from Eastern Sierra streams. Freshwater evaporating from the lake each year has left the salts and minerals behind so that the lake is now about 2 1/2 times as salty and 80 times as alkaline as the ocean. Tufa Towers was the result of nature's work. This high elevation lake at nearly 6400 feet is a perfect ecosystem environment for visiting birds. Alkali flies and their larvae and pupae thrive on the lake's edge providing food for the migrating birds. Brine shrimp is also on the menu for these birds. Be sure to read the educational image verbage within the gallery.