Mesa Verde, Colorado

Cliff Palace, ca. 1931. Photograph NAU.PH.95.48.596 by Barbara or Edwin McKee.  Courtesy of Cline Library Special Collections, Northern Arizona University

In 1906 Mesa Verde National Park became the first park set aside for the "preservation of the sites and the other works and relics of prehistoric man." Today its importance as a focal point of research on Anasazi culture and land use cannot be overestimated. In 1978 it was designated a World Heritage Cultural Site by UNESCO.

In archaeology, the term Mesa Verde is also used to refer to Anasazi architecture, masonry, and pottery of the Four Corners area. The density of sites in the region is astonishing. Southwestern archaeologist Douglas Bowman has said, "If there were a stake in place for every Anasazi site in the Four Corners, one could see thousands of stakes in every direction!" On Mesa Verde alone it has been estimated that there would be some 12,000 markers. This estimate was made before a fire in 1996 cleared almost 5000 acres of vegetation in the park and revealed that the density of undocumented sites is far greater than previously thought.

Mesa Verde is a high plateau with a north escarpment rising nearly two thousand feet from the valley below. Formed by uplifting, the mesa tilts upward from south to north. More than twenty canyons cut the Mesa and drain into the Mancos River. A layer of shale beneath two layers of porous sandstone allows moisture from rain and snow to follow the hard surface of the shale to the canyon walls, resulting in numerous seeps and springs. Alternate freezing and thawing of this water created the famous overhangs and alcoves by loosening the lower sandstone slabs and causing them to break away from the cave ceilings. In these alcoves, the Anasazi built some of the most notable and best preserved cliff dwellings found in the United States.

Human occupation of Mesa Verde began between A.D. 550 and 750. These descendants of the earlier Basketmakers, who did not leave an archaeological record at Mesa Verde, were more dependent on agriculture than their nomadic predecessors. They began building permanent semi-subteranean houses, known as pithouses, in the alcoves as well as on the mesa top during this period. About 750 they began building houses above ground, with upright walls made out of poles and mud. From this period on, these people were known as Pueblos, a Spanish word for village dwellers. By 1000, the people of Mesa Verde had advanced from pole-and-adobe construction to skillful stone masonry, and farming provided more of their diet than before, with much mesatop land cleared for that purpose.

The years from 1100 to 1300 were Mesa Verde's Classic Period. The population, which may have reached several thousand, was mostly concentrated in compact villages of many rooms, often with the ceremonial kivas. About 1200 there was a major population shift. The people began to move back into the cliff alcoves that had sheltered their ancestors long centuries before. Most archaeologists now consider the move to be an adaptation to climate change, specifically a succession of droughts which were especially severe in the Four Corners area. Social or religious conditions may also have changed. Structures such as Balcony House suggest that defense may have been on the minds of the builders, but the defense may have been against spiritual rather than human forces. Whatever the reason or combination of reasons, it gave rise to the cliff dwellers for which Mesa Verde is today most famous.

Most of the cliff dwellings seen today were built from the late 1190s to the late 1270s. They range in size from one-room houses to villages of more than 200 rooms (see photograph above). The Anasazi lived in the cliff dwellings for less than 100 years. By about 1300 Mesa Verde was deserted. There are several theories about the reason for the migration. Paleoclimatic studies indicate that the last quarter of the 13th century was a time of drought and crop failures. Almost certainly, after hundreds of years of intense use, the surrounding land and its resources were depleted. Under such environmental stress, there were probably some significant social and political problems. The people of Mesa Verde apparently traveled south into New Mexico and Arizona at this time, where today Pueblo people, and perhaps other tribes, are considered likely descendants of the Mesa Verde cliff dwellers.

--Researched and written by Shannon Kelly

Floyd, M. Lisa, William H. Romme, David Hanna. 1999. Fire history and vegetation pattern in Mesa Verde National Park, Colorado. Submitted to Ecological Applications.

Floyd-Hanna, M. Lisa, Wlliam H. Romme. 1993. Biological invasions after fire, Mesa Verde National Park. Park Science 29: 12-14.

Floyd, M. Lisa, David D. Hanna, Allan Loy, William H. Romme. 1999. Weed invasion after fire: a weed risk model incorporating pre-fire vegetation and post-fire treatment in Mesa Verde National Park. Submitted to Conservation Biology.

Floyd, M. Lisa, William H. Romme, Marilyn Colyer, David Hanna, and Albert Spencer. 1999. Ancient pinon-juniper woodlands of Mesa Verde: Toward a definition of old-growth. Submitted to Natural Areas Journal.

Romme, William, L. Floyd-Hanna, and M.Conner. 1993. Effects of fire on cultural resources at Mesa Verde National Park. .Park Science 13: 28-30.