San Nicolas Island is the most remote of California's Channel Islands, located 61 miles (98 km) from the nearest point on the mainland coast. It is part of Ventura County. The 14,562 acre (58.93 km2 or 22.753 sq mi) island is currently controlled by the United States Navy and is used as a weapons testing and training facility, served by Naval Outlying Field San Nicolas Island. The uninhabited island is defined by the United States Census Bureau as Block Group 9, Census Tract 36.04 of Ventura County, California. The Nicoleño Native American tribe inhabited the island until 1835. As of the 2000 U.S. Census, the island has since remained officially uninhabited, though the census estimates that at least 200 military and civilian personnel live on the island at any given time. The island has a small airport and several buildings, including telemetry reception antennas.
Archaeological evidence suggests that San Nicolas Island has been occupied by humans for at least 10,000 years. For thousands of years, San Nicolas was the home of the Nicoleño people, who were probably related to the Tongva of the mainland and Santa Catalina Island. It was named for Saint Nicholas by Spanish explorer Sebastián Vizcaíno after he sighted the island on the saint's feast day (December 6) in 1602. The Nicoleños were evacuated in the early 19th century by the padres of the California mission system. Within a few years of their removal from the island, the Nicoleño people and their unique language became extinct.