The California Desert Protection Act of 2010 adds approximately of land to the National Park System. The additions to Death Valley National Park total approximately . The largest parcel (31,000 acres/48 sq mi/130 km2) is known as the Bowling Alley—a narrow strip of land between the southern boundary of the park and Ft. Irwin that was designated a wilderness study area by the California Desert Protection Act of 1994. The Crater Mine Area (6,400 acres/10 sq mi/26 km2) is a former sulfur mining area in northern Death Valley that is entirely surrounded by Park wilderness. The bill adds a area containing the Castle Mountains on the border of Nevada to the Mojave National Preserve. This land was left out of the original California Desert Protection Act that created the preserve due to an open-pit gold mine that was still active in 1994. The mine has since been closed and the mining company has largely restored the land. The bill adds approximately to Joshua Tree National Park in the form of multiple small parcels of BLM land on the northern boundary of the park that have been identified for disposal.