Archaeologists believe the first Indians to arrive on the Pajarito Plateau were Keres speakers, who came from Arizona between 1175 and 1250 A.D. They built homes of volcanic tuff blocks where small groups of three or four families might live together. Some also lived in the natural caves of the canyon walls. Remains of these dwellings, usually from eight to twenty rooms, can be found all over the plateau. Members of Keresan-speaking pueblos such as Cochiti and others to the south and west of Los Alamos are thought to be the descendents of these early settlers.
Around 1300 A.D., a second migration of natives from the Four Corners area, including the spectacular towns of Mesa Verde and Chaco Canyon, moved onto the Pajarito Plateau. They introduced the Tewa language and constructed large community dwellings on the mesa tops, from one to four stories high with as many as 600 rooms. They also carved out artificial caves from the canyon walls to create multiple cliff dwellings.
Within 50 years of their arrival, the Tewas began to drift away. Drought and raids by Navajos, Utes, Apaches, and Commanches were the cause, according to the oral traditions of San Ildefonso and Santa Clara pueblos, home to Tewa speakers today. Archaeologists also cite a drop in average temperature, which shortened the growing season and caused food shortages. The movement, however, was gradual. By 1550, Indian settlers had abandoned the Pajarito Plateau for pueblos along the Rio Grande, where warmer temperatures and irrigation made farming easier. The natives would, however, return to the plateau to hunt and worship.
Remains of both Tewa and Keres-style dwellings can be seen today at Bandelier National Monument. A small Ancestral Pueblo site, often excavated by boys from the Los Alamos Ranch School, sits near the Los Alamos History Museum. In addition to their dwellings, the Indians left behind thousands of petroglyphs, carvings into rocks, which can be found throughout the canyons of the Pajarito Plateau.
More information on the prehistoric period of Los Alamos can be found in Los Alamos, New Mexico: A Survey to 1949; Sentinels on Stone, the Petroglyphs of Los Alamos; and A Guide to Bandelier National Monument, publications of the Los Alamos Historical Society. Please visit our Shop for information on these and other books about the natural and cultural history of Los Alamos.