Navajo National Monument in northern Arizona preserves three major Ancestral Puebloan cliff dwellings above the Tsegi Canyon system: Keet Seel, Betatakin, and Inscription House. Created in 1909 and later reduced to three tracts around the ruins, it protects communities built mainly in the late 13th century as Pueblo people concentrated in sheltered settlements. Keet Seel and Betatakin were substantial sandstone, mud, and wood villages with kivas, storage rooms, and tightly clustered living spaces, supported by agriculture in a difficult high-desert environment. Their abandonment near the end of the 13th century is linked to drought and environmental strain, though Hopi tradition connects it to conflict and spiritual migration.