[2] Established in 1964 by the Wilderness Act and named for naturalist John Muir, it encompasses 652,793 acres (2,641.76 km2).

[1] The wilderness lies along the eastern escarpment of the Sierra from near Mammoth Lakes and Devils Postpile National Monument in the north, to Cottonwood Pass near Mount Whitney in the south.

[3] The peaks are typically made of granite from the Sierra Nevada Batholith, and are dramatically shaped by glacial action.

The John Muir Wilderness contains the largest contiguous area above 10,000 feet (3,000 m) in the continental United States.

[4] Common animals in the wilderness include yellow-bellied marmots, pikas, golden-mantled ground squirrels, Clark's nutcrackers, golden trout, and black bears.