Hohokam petroglyphs near the Signal Hill, Saguaro National Park. The Hohokam people lived in the Sonoran Desert for hundreds of years. They had a fairly advanced civilization from about 750 A.D. to 1450 A.D. and built large structures and walled villages, traded with many other nations, and developed irrigated agriculture to grow corn, beans, and other crops. Around 1450 the people abandoned their permanent structures and assumed a nomadic, hunter-gatherer style of living. They are the ancestors of the Tohono O'odham people that live in the area today.

It is not known whether the purpose of the petroglyphs was ceremonial, artistic, or some combination of uses. The artifacts at this site are estimated to be about 800 years old. There are examples of both abstract geometric and spiral designs as well as depictions of animals and people. The petroglyphs are in very good condition and certainly evoke wonder and respect for their age and their significance to the original creators.