Featuring massive Ancestral Puebloan buildings set in an isolated high-desert environment, intriguing Chaco contains evidence of 5000 years of human occupation. In its prime, the community at Chaco Canyon was a major trading and ceremonial hub for the region - and the city the Puebloan people created here was masterly in its layout and design. Pueblo Bonito is four stories tall and may have had 600 to 800 rooms and kivas