The approximately 600 cliff dwellings in Mesa Verde National Park represent the apex of architectural sophistication of the Northern San Juan Anasazi culture.
The cliff dwellings, the final product of 600 years of cultural development on the Mesa Verde, were built between CE 1200 and 1300, and were abandoned shortly thereafter. The spectacular setting and the well-preserved state of these structures resulted in Mesa Verde being the first nomination by the United States government to the World Cultural Heritage Sites List. Moreover, descendants of these ancient peoples, the Pueblo Indians of Arizona and New Mexico, continue to venerate these sites, representing a cultural continuity unique for North America and much of the world. Excavation and preservation has been continuous since Mesa Verde became one of the first National Parks in 1906. The structures interpreted to the public have been preserved over the years with a minimum of repair and replacement, resulting in a cultural resource of great integrity and authenticity. A renewed project of conservation and site management developed by the Architectural Conservation Laboratory of the University of Pennsylvania and the National Park Service is now underway as part of the Save America's Treasures Program for 2000-2002.