High Quality Content by WIKIPEDIA articles! Rincon Island is an artificial island located off Rincon Beach in Ventura County, California on public land leased from the California State Lands Commission (CSLC). The island is situated approximately 1,000 feet (300 m) offshore in 55 feet (17 m) of water. The island was constructed in 1958 for the specific purpose of well drilling and oil and gas production. It is near the seaside communities of Mussel Shoals and La Conchita. The island is connected to the mainland by the Richfield Pier.