Spectacular ruins such as those of Mesa Verde and Chaco Canyon claim the most public attention, but it was a far less impressive ruin on the eastern edge of Pueblo country that yielded evidence crucial for reconstructing Anasazi culture history in the entire Southwest (Fig. I). A.V. Kidder’s excavations in Pecos Pueblo trash mounds yielded one thing among several important results. His excavations recovered evidence of Puebloan contact with Plains people beginning in the prehistoric period and reaching a climax in the mid-1500s (Kidder 1924, 1932). At that point, Spanish accounts began to add rich detail to the story of Plains-Pueblo interaction. A further possibility seemed clear. If evidence of Plains-Pueblo contact was present at Pecos, might it not be present at other pueblo sites on the border of the Plains? In 1957 our immediate interest was focused on the abrupt mountain-plains transition of northeastern New Mexico. Here, we hoped to find and identify historically documented villages of Jicarilla Apaches, and we sought to learn how easy access to two different environments might be reflected archaeologically.