Human presence in Horseshoe Canyon has been dated as far back as 7000-9000 B.C., when Paleo-Indians hunted large mammals such as Mastodons and Mammoths across the southwest.
Later inhabitants included the Desert Archaic culture, the Fremont culture, and Ancestral Pueblo People.
Occupation by the Fremont and Ancestral Puebloans was relatively brief; it is believed that the canyon was abandoned by Native American peoples by 1300 A.D.
The Great Gallery is one of largest and best preserved collections of Barrier Canyon Style rock art in the United States.
The gallery was a product of the Desert Archaic culture, a nomadic group of hunter-gatherers predating the Fremont and Ancestral Puebloans.
The panel itself measures about 200 feet (61 m) long and 15 feet (4.6 m) high. The panel contains about 20 life-sized anthropomorphic images, the largest of which measures over 7 feet (2.1 m) tall.
Reproductions showing the haunting beauty of the paintings are in the Museum of Modern Art in New York and the Denver Natural History Museum.