The Lehner Mammoth-Kill Site is a location in southern Arizona that is significant for its association with evidence that mammoths were killed here by Paleo-Indians 9000 years BCE. In 1952, Ed Lehner discovered extinct mammoth bone fragments on his ranch, at the locality now known as the Lehner Mammoth-Kill Site. He notified the Arizona State Museum, and a summer of heavy rains in 1955 exposed more bones. Excavations took place in 1955–56, and again in 1974–75. In the first season, two Clovis projectile points were found among the ribs of a young mammoth.