In September 2000, I went to Chaco Canyon, New Mexico, to work on a book about the ancient Puebloan people who had lived in great houses here a thousand years ago. I was accompanied by Dr. Gwinn Vivian, an archaeologist who had grown up excavating these sites with his father, who was also a Chaco Canyon archaeologist. These ruins are still a mystery to scientists, but we do know that they were left by the ancestors of the Zuni, Hopi, and Rio Grand pueblos.