South Fork Group Campground is the largest group camping facility in the Crystal Basin Recreation Area, situated at 5,200 feet elevation between Union Valley Reservoir and Loon Lake with the South Fork of the Rubicon River within walking distance for fishing and swimming.

The primitive campground accommodates up to 125 people with a group cooking area, vault toilets, and campfire rings, but has no drinking water on-site—visitors must bring their own water or treat stream water.

Access is via a gated road (combination provided after reservation), and the remote location requires advance planning for a true backcountry experience.