The cultural resources administered by the Bureau of Land Management in Arizona are some of the most important and best preserved prehistoric and historic archaeological sites in the American Southwest. These sites span the entire range of human occupation in the New World, from 13,000 years ago to the present. They include properties as diverse as Paleo-Indian mammoth kill sites, Archaic hunting camps, giant ground figures (intaglios), pueblo ruins, rock art, ghost towns, historic ranches, and numerous historic trails and wagon roads such as the Butterfield Overland Stage Route. Nineteen individual properties and Districts are listed on the National Register of Historic Places, and one is a National Historic Landmark. More than 750,000 acres of Arizona public land have been inventoried for cultural resources, and nearly 11,000 sites recorded. (See also: BLM America's Priceless Heritage: Cultural and Fossil Resources on Public Lands, Arizona" (November 2003) )
Eighteen cultural properties have been interpreted and developed for public visitation. Among these are the giant Blythe Intaglios along the Colorado River, the 18th Century Spanish Presidio of Santa Cruz de Terrenate, the historic copper mining town of Swansea, the turn-of-the century Harquahala Peak Smithsonian Solar Observatory, Little Black Mountain Rock Art Site, the Murray Springs Clovis Site where Early Americans killed and butchered mammoth and bison, the 1776 trail of Spanish friars Dominguez and Escalante, the Anza National Historic Trail which is a designated Millennium Trail, and the historic 130-year-old Empire Ranch.
Twelve Areas of Critical Environmental Concern (ACECs), comprising nearly 227,000 acres, were designated entirely or partly to provide special management attention to protect cultural resources. Three National Conservation Areas (NCAs): the San Pedro Riparian NCA, the Gila Box Riparian NCA, and the Las Cienegas NCA, contain numerous significant cultural properties, including the Lehner Mammoth Kill site, a National Historic Landmark. In 2000 and 2001, five new National Monuments were designated, providing special protection and recognition for nearly 2 million acres of BLM-administered lands containing hundreds of highly important cultural properties such as pueblo ruins.