About
Just west of downtown Tuscon stands Tumamoc Hill, also known as Chemamagi Du’ag, or Horned Lizard Mountain. It is a volcanic butte with deep scientific and historic significance.
The site is an 860-acre ecological reserve and U.S. National Historic Landmark. Established by the Carnegie Institution in 1903, it became home to an early desert laboratory, created to study how plants adapt to desert conditions. The University of Arizona owns and manages much of the site, and it is still an active research location.
Not just a spot for ecological research, Tumamoc Hill has a history of human activity that runs much deeper. Radiocarbon dating places early maize cultivation at around 4,100 years ago, which makes it the longest continuously inhabited site in the United States. The area was also once home to the Hohokam people, starting around the the year 400; this culture left behind petroglyphs and pottery fragments. The Tohono O’odham Nation, for whom Tumamoc Hill still holds sacred significance, descends from this group.
Today, the site is not just used for research—but recreation. About one-thousand people walk the hill each day, taking in the scenic views of the surrounding desert landscape. It is a three-mile round trip walk, with a 700-foot rise in elevation from bottom to top.
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Know Before You Go
You can walk Tumamoc Hill’s paved road anytime between 4 a.m. and 10 p.m. There are benches along the way, with a portable toilet and water fountain placed at the midpoint.
Bring plenty of water, sunscreen, and a flashlight (if you’re walking early enough in the morning or late enough in the evening).
Sponsored by Visit Tucson.
Published
April 25, 2025
