Chaco is one of many great archaeological sites scattered throughout the Southwest, though what makes it exceptional is the culture that emerged here and flourished over centuries. Chaco Culture is inscribed on a single criteria: (iii) to bear a unique or at least exceptional testimony to a cultural tradition or to a civilization which is living or which has disappeared. The diverse native traditions and histories today in the region do not necessarily perceive the Chacoan culture as "disappeared" and in fact view sites at Chaco Canyon, Mesa Verde, and other cultural sites as interconnected to the stories and living traditions of their people today.
I thoroughly enjoyed my visit here in May 2010 and to the Aztec Ruins component in November 2022. The complex of sites of "Chaco Culture National Historical Park" are large and spread out within the canyon. Half a day is appropriate to see all the sights. The exceptional passageways, doors, and kivas are some of the best preserved anywhere in the Southwest.
Aztec National Monument is not too far away and it's certainly worth your time. As the other essential component to the Chaco Culture world heritage site, the Aztec Ruins located near the Animas River operated as a regional center that may have flourished even after the great Chacoan houses to the South declined. There are only a few 'other" visitable components (besides Chaco Canyon/Aztec Ruins) for keen travellers seeking a complete experience. Pueblo Pintado or Kinteel "wide house" which is located 16 miles Southeast of Pueblo Bonito (Chaco Canyon) and is accessible by an unpaved road well eastward of the National Park site. Casamero Pueblo (located a few miles North of Prewitt) and accessible via paved road and a small parking lot, includes information panels.
Lowry Pueblo (Colorado), a key Puebloan site about 160 kilometers North of Chaco Canyon would be a fine extension to the Chaco Culture WHS. Located in the aptly named "Canyon of the Ancients National Monument", Lowry Pueblo is widely considered a key Northern'most' terminus of Chaco Culture and the presence of a "great kiva" suggests its regional importance. Lowry Pueblo does not align on the North/South axis of the other inscribed Chacoan sites and its layout and architectural elements seemingly reflect cultural influences from both Chaco Culture and Mesa Verde.