I have made pilgrimages to sacred sites throughout North America, but the Great Kiva Casa Rinconada in Chaco Canyon, New Mexico is the most powerful place I have ever drummed. A Great Kiva is a large, circular, usually subterranean structure that was designed and used by Anasazi peoples for ceremonial and communal gatherings. The two masonry box-like vaults found on the floor of most Great Kivas are believed to have been covered with planks and served as foot drums. I first drummed here in 1991 when the NPS still allowed entry into the kiva. The sonic phenomena within a kiva transcend the usual range of auditory experience. The walls of the stone structure reflect, amplify, and transform the sounds of the drum, resulting in some extraordinary harmonics. Drum sounds become distorted and seem to expand and move around the chamber due to an acoustic phenomenon known as standing waves. As sound waves reverberate between the walls, they either cancel or combine, causing certain resonant frequencies to either completely disappear or intensify, change in pitch, and develop vibrato. Within a kiva, it is possible to compose an entirely new auditory universe from the architecture of sound itself. Click here for a guide to Anasazi sites of the Southwest.