San Rafael Ranch State Natural Area is a 35-square-mile expanse of rolling short-grass prairie crossed by the natural riparian corridor along the Santa Cruz River. San Rafael Ranch is a cooperative venture between Arizona State Parks and the Nature Conservancy to keep this undeveloped valley with its rare native plants and animals as pristine as possible.

Approximately 15 miles of county roads enter the property at four different points and, for now, only picture taking of the scenic valley is allowed. The property itself is not yet open to the public. The Nature Conservancy holds 17,000 acres under a conservation easement that guarantees the land will remain pristine and never be developed. Arizona State Parks bought 3,550 acres of the southern part of the ranch around the ranch homestead with its pre-territorial houses, barns, corrals, blacksmith shop, and windmills. Arizona State Parks plans to offer a historic house tour and develop a series of nature walks on the property in the future.

San Rafael Ranch State Natural Area is about 23 miles southeast of Patagonia on the Santa Cruz River.