The Pryor Mountains to the east cover roughly 300,000 acres. Once entirely Crow Indian territory, now only the north end of the range is on the Crow Reservation, while the south end is in the Custer National Forest. The range is bound on the east by Bighorn Reservoir and on the south by the Pryor Mountain National Wild Horse Range. The mountains were named indirectly for Pryor Creek, which Captain William Clark named for Lewis and Clark Expedition member Sergeant Nathaniel Pryor. The Pryors contain features including ice caves, sinks, and caverns, and archaeological finds such as Clovis Points indicate human occupation as long ago as 10,000 years ago. In the south end of the range, remains of log and frame houses and barns attest to homesteads staked after passage of the Forest Homestead Act in 1906. Though some crops were cultivated, for many homesteading was a pretense for mountain grazing on adjacent forest and reservation ranges, and one forest ranger observed that some claimants had applied for places where it would be impossible to winter over, though to hear them talk "one would think that Pryor Mountain contained the biggest part of the Banana Belt and that pineapples grew wild."