Crabtree Hot Springs, California, Natural hot spring in Lake County, California

Crabtree Hot Springs is a cluster of four natural hot springs in a narrow, steep-walled canyon on the north bank of the Rice Fork of the Eel River, about a quarter mile downriver from its junction with Salt Creek. Three springs sit together at a large swimming hole; the fourth lies about 60 feet upriver. The hottest reaches 106 °F (41 °C) at roughly 10 gallons per minute, emerging in a natural rock basin at the foot of a small cliff.

Orin Crabtree found the springs around 1875 by following a Native American trail; his father John Fletcher Crabtree moved to Twin Valleys about 1890 and built a home 150 yards southwest of the Rice Fork and Salt Creek junction. Around 1907 Upper Lake businessman Samuel Tate Packwood bought property at the springs and planned a resort, reopening the wagon road. Orin sold to the Dixon Gun Club in 1920.

The springs were a spa for local Native Americans, who reached them by a well-used trail from Upper Lake; the large boulder at the springs is called Medicine Rock. John Fletcher Crabtree, who found the springs about 1875 by following a Native American trail, invited whites to bathe for the water's purported medicinal properties, and some brought sick horses and swore by the results.

The springs lie on private property and are closed to the public, so access cannot be assumed. The only approach is a quarter-mile trail from Twin Valley Road (forest road 17N04) at the junction of Rice Fork and Salt Creek, following the river on its north side. The canyon is narrow, steep-walled and isolated, and the old wagon road was abandoned and became impassable before Packwood reopened it.

The hottest spring releases warm water from serpentine rock formations at a steady flow rate year-round. This geological feature draws visitors interested in natural thermal phenomena and the geology of the region.