The Southwest is filled with living and long disappeared Native American cultural sites and Mesa Verde is an absolute must when visiting the region. I visited Mesa Verde National Park twice, once in 2009 and a second time in 2014. The national park is large enough that during my second visit much of what I explored was new. This would be ideal as a mixed property, but when it was inscribed that was not thought of yet.
Like much of the Ancient Puebloan cultures in the Southwest, the story of these sites are one we are still trying to better understand today, particularly their relation with other peoples of the North American continent. They built massive structures, practiced astronomy, traded with coastal peoples in California, and established trade routes extending to Mesoamerican cultures.
To me, Mesa Verde and specifically "Cliff Palace" is America's Parthenon, a grand structure designed by master architects that should be more well-known. Mesa Verde along with Chaco Culture, Taos Pueblo, Canyon of the Ancients, Bears Ears, Canyon de Chelly, and Monument Valley in the Four Corners region are some of the most exceptional Native American sites in the United State and highly rewarding for any curious visitor.