Claim: Bouldin Island, an island located in Northern California, has a total land area of 5,900 acres (2,400 ha).
Evidence: The 2,400 ha (5,900-acre) island is bounded to the north by South Mokelumne River which separates the island from Staten Island. Bouldin Island is an island in the Sacramento-San Joaquin River Delta in San Joaquin County, California, 20 kilometers (12 mi) northwest of Stockton on the Stockton Deepwater Shipping Channel. The county is located in Northern California's Central Valley just east of the very highly populated nine-county San Francisco Bay Area region and is separated from the Bay Area by the Diablo Range of low mountains with its Altamont Pass. 
5,900 acres (2,400 ha) Bouldin Island is an island in the Sacramento-San Joaquin River Delta in San Joaquin County, California, 20 kilometers (12 mi) northwest of Stockton on the Stockton Deepwater Shipping Channel. The county is located in Northern California's Central Valley just east of the very highly populated nine-county San Francisco Bay Area region and is separated from the Bay Area by the Diablo Range of low mountains with its Altamont Pass.