Rising to just over 6,000 feet, the McCullough Peaks are an area of desert badlands which lie just to the south of Powell.
Like their more famous neighbor, Heart Mountain, they were formed by the erosion. Ancient geologic activity cast harder rock on the relatively soft dirt of the ancient Big Horn Basin floor. Wind and rain sculpted the McCullough Peaks as the softer underlying soil was washed and blown away.
The peaks are named after Peter McCulloch, foreman for William Carter, who established one of the first cattle ranches in the Big Horn Basin south of Cody in the early 1880's. (The name is spelled "McCullough Peaks" on U.S. Geological Survey Maps.)
The Shoshone River, and the irrigation for all of the Powell Valley, runs just to the north of the Peaks.
Bands of wild horses live in the Peaks, as well as numerous deer and antelope. Mountain lions also inhabit the area.
The area is rich in fossils from the Eocene Epoch, some 38 to 58 million years ago. The climate was warm and wet, and this part of Wyoming was covered with trees and swamps. Fossils of crocodiles, lemurs, and numerous archaic mammals are common.