Mesa Verede National Park is both a national park and a UNESCO World Heritage Site. It preserves and interprets a large collection of ruins left by Ancestral Puebloans. The sites was occupied from 450-1300 A.D. The cliff dwellings that we know it for were only built in the last 100 years of that time period. This video shows a tour of Cliff Palace.

For more information read https://amateurtraveler.com/denver-to-mesa-verde-and-durango/