The Mokelumne Wilderness is a 105,165-acre (164 sq mi; 426 km2) federally designated wilderness area located 70 miles (110 km) east of Sacramento, California. It is within the boundaries of three national forests: Stanislaus, Eldorado and Toiyabe. First protected under the Wilderness Act of 1964, the Mokelumne's borders were expanded under the California Wilderness Act of 1984 with the addition of 55,000 acres. The wilderness takes its name from the Mokelumne River, which was named after a Mi-wok Indian village located on the riverbank in California's Central Valley.