The excavation of Oriyo Timbo marked the beginning of a substantial research partnership between the Gujarat state Department of Archaeology and the University Museum of the University of Pennsylvania. The site, located in Chiroda village, Gadhada, Bhavnagar district of Gujarat state was first visited by archaeologists in 1971. This report is a review of the one season of excavation at the site and is complemented by a more detailed study of the animal bones, especially an analysis of the annular rings in mammal teeth prepared by Paul Rissman.