Mono County is located in the east central portion of the U.S. state of California. The county seat is Bridgeport. The only incorporated city in the county is Mammoth Lakes. Mono County was formed in 1861 and named after Mono Lake which, in 1852, was named for a Native American Paiute tribe that inhabited the Sierra Nevada from north of Mono Lake to Owens Lake. The county has a total area of 3,132 mi², 97% of it is land and 3% of it is water. As of 2000, there were 12,853 people, 5,137 households, and 3,143 families residing in the county. The population density was 4/mi². The median income for a household in the county was $44,992.