In recognition of its rich archaeological resources, Chaco Culture NHP is listed in the National Register of Historic Places and was designated a UNESCO World Heritage Site in 1987. Chaco’s national and international significance is based on its approximately 4,000 prehistoric and historic archaeological sites, representing more than 10,000 years of human cultural history in Chaco Canyon. These sites document:
- Evidence of a civilization that flourished between the 9th and 13th centuries and attained remarkable achievements in architecture, agriculture, social complexity, engineering, astronomy, and economic organization.
- Chaco “great houses” -- the largest, best preserved, and most complex prehistoric architectural structures in North America. Sixteen great houses are interpreted within the park.
- A regional system of communities, centered in Chaco Canyon and linked by prehistoric road and trade networks throughout the San Juan Basin.
- 120 years of archaeological and anthropological research in the park that has yielded a systematic record of the lifeways and environment of the region's former inhabitants, and resulted in the accumulation of more than 1.5 million artifacts and archival documents that are curated for purposes of furthering scientific inquiry and public education.
- In addition to its archaeological legacy, Chaco Culture NHP preserves other links to the past and to the natural landscape throughcontemporary American Indian descendants of Chaco Canyon, whose traditional oral histories tell of their time in Chaco Canyon and who value it today for its spiritual connection to their past.
- A remote location that offers outstanding opportunities to enjoy solitude, natural quiet, clear air, starlit night time skies, and panoramic vistas of the scenic sandstone outcrops into which Chaco Canyon is carved.
- The largest long-term protected natural area in northwestern New Mexico, which encompasses relatively undisturbed examples of floral and faunal communities within the Colorado Plateau ecosystem, and offers unparalleled opportunities to conserve the region’s biodiversity and monitor its environmental quality.