It includes Chaco Culture National Historical Park, the associated sites at Aztec Ruins National Monument, and five additional protected archaeological areas. IntegrityWithin the boundaries of the property are located all the elements necessary to understand and express the Outstanding Universal Value of Chaco Culture, including walls built of sandstone and mud mortar standing more than five storeys tall, pine roof beams, and well-preserved archaeological remains that provide a comprehensive picture of the Chaco culture, all having survived due to high-quality craftsmanship and the dry, remote location. Protection and management requirementsThe property is comprised of the acreage to which the federal government had surface title in 1987 located within seven components: Chaco Canyon, formerly a National Monument (1907) and now Chaco Culture National Historical Park (1980); Aztec Ruins, a National Monument (1923, expanded in 1928, 1930, 1948, 1988); and five Chaco Culture Archaeological Protection Sites (1980). The inclusion of Chaco Canyon and Aztec Ruins in the National Park system gives them the highest possible level of protection, and assures them a high standard of interpretation and public access. The five Chaco Culture Archaeological Protection Sites are owned and managed for conservation by the Bureau of Land Management, a sister agency in the U.S. Department of the Interior.