Chimney Rock National Monument protects a significant archaeological landscape in southwestern Colorado centered on Chimney Rock and Companion Rock, where an Ancestral Puebloan community flourished from about AD 925 to 1125. Closely tied to Chacoan culture, the site is especially known for the Great House Pueblo, likely built and expanded during lunar standstills that gave ceremonial meaning to the moon’s appearance between the rock formations. The community included dwellings, work areas, kivas, and access-control structures that reveal both daily life and ritual activity. Abandoned around 1125, the site remains sacred to modern descendants and is preserved for protection, interpretation, and education.