In addition to its remarkable public and ceremonial buildings the Ancient Puebloans built numerous roads, ramps, dams, and mounds, which required a great deal of well organized and skillful planning, designing, resource gathering, and construction. The distinctive architecture combines a number of designs, astronomical alignments, geometry, landscaping, and engineering to create an ancient urban center that continue to amaze archeologists and visitors a thousand years later.

Archaelogic evidence suggests that the Ancient Puebloans had been occupying the area as early as 1200 B.C. when they survived as nomadic hunters and gatherers, hunting with wood clubs, hunting sticks and spears..  Some three centuries later, they began to make more permanent homes in caves and pit houses where they  constructed numerous woven baskets that were covered with mud and baked to make water proof containers. Archaeologists identify these first people as Basketmakers

About 700 A.D. the Ancient Puebloans began cultivating crops, such as corn and squash, and building permanent dwellings.  These small, one-storied, masonry structures were the beginning of what would become the great pueblos of the southwest.

Some two centuries later, as their population grew, the communities expanded into larger, more closely compacted pueblos. It was around this time that the Pueblo Bonito complex was built, beginning with one curved row of rooms near the north wall.  Continuing to refine their building techniques, the use of thick masonry walls and the generous use of mud mortar allowed walls to rise to more than four stories in height.

More pueblos, including Chetro Ketl, Una Vida, Penasco Blanco, Hungo Pavi, and Kin Bineola were started at about this time. Some large buildings show signs of being planned from the start, in contrast to the usual Ancient Puebloans custom of adding rooms as needed. For the next two centuries, more and more of these large pueblos with oversized rooms began to be built throughout the region.  Eventually, there were an estimated 75 villages in the area, tied together by an extensive system of roads.

From the twelfth to the thirteenth centuries, many of the pueblos in Chaco Canyon were abandoned when a long cycle of drought began in the San Juan Basin.  The Ancient Puebloans were at their height of civilization when the lack of rainfall led to food storages.  Even though they had designed an extensive system of dams and irrigation methods, the dry climate and overtaxed fields could no longer support the immense population.  As famine spread throughout the area, the people began to leave, joining other pueblos in the south and east near the Little Colorado and the Rio Grande Rivers.

Some archaeologists now believe that other factors, such as religious upheaval, internal political conflicts, and warfare may have also contributed to the abandonment.  By the 1300's, all of the villages and pueblos of Chaco Canyon were abandoned.  As the ancient Indians left, their kivas were ceremonially burned and most of their possessions were left behind.

In 1949, the University of New Mexico deeded lands in Chaco Canyon National Monument to the National Park Service, in exchange for continued rights to conduct scientific research in the area. By 1959, the National Park Service had constructed the park visitor center, staff housing, and campgrounds. In the 1970's, a number of research projects, archaeological surveys, and limited excavations began which provided extensive information about the ancient Ancient Puebloans. 

Archeological excavations in Chaco Canyon today are limited, as modern methods such as remote sensing now allow archaeologists to gather a great deal of information without disturbing the fragile and irreplaceable sites.

Chaco Canyon courtesy National Park Service