Mesa Verde National Park - http://www.nps.gov/meve
Mesa Verde, Spanish for "green table", offers an unparalleled opportunity to see and experience a unique cultural and physical landscape. The culture represented at Mesa Verde reflects more than 700 years of history. From approximately A.D. 600 through A.D. 1300 people lived and flourished in communities throughout the area, eventually building elaborate stone villages in the sheltered alcoves of the canyon walls. Today most people call these sheltered villages "cliff dwellings". The cliff dwellings represent the last 75 to 100 years of occupation at Mesa Verde. In the late 1200s within the span of one or two generations, they left their homes and moved away.
The archeological sites found in Mesa Verde are some of the most notable and best preserved in the United States. Mesa Verde National Park offers visitors a spectacular look into the lives of the Ancestral Pueblo people. Scientists study the ancient dwellings of Mesa Verde, in part, by making comparisons between the Ancestral Pueblo people and their contemporary indigenous descendants who still live in the Southwest today. Twenty-four Native American tribes in the southwest have an ancestral affiliation with the sites at Mesa Verde.