The Omo site group has seen intensive study since it was first visited in 1983 by archaeologists Michael Moseley, Robert Feldman, and myself. Omo is a multicomponent settlement group in which three distinct Tiwanaku ceramic styles are represented at five distinct bluff top settlement areas (designated M10, M11, M12, M13 and M16. Omo is located approximately ten kilometers south of the modern city of Moquegua, atop bluffs that overlook and control a wide expanse of valley bottom land, desert caravan routes, and the region's most productive natural springs.

Tiwanaku state style architectural remains and artifact scatter cover over 38 hectares (382,630 m2), with an additional 6 hectares of local Tumilaca Phase occupation. This makes Omo the largest of the Moquegua Tiwanaku site groups.

I first worked at habitation sectors of the Omo site group in 1984 and 1986-1987, followed by a separate project at the Omo M10 temple in 1990. In 1999, I co-directed excavations at the M16 site when it was endangered by agricultural development.

Site Groups: M10, M11, M 12, M13, M16