This report summarizes excavations conducted within two adjoining Operations, Op. 31 and Op. 56, on the northern edge of the site of La Sierra. The material recovered here dates primarily to the Late (AD 600-800) and Terminal Classic (AD 800-1000). These two suboperations are described together because of their proximity and because the recovered constructions are thought to have been closely involved in the activities conducted across this portion of La Sierra.
Schortman, Edward, "PVN OP 031 and 056 Excavation Report" (1990). Four Valleys Archive. Paper 21487.
Op 31 and 56