The Lehner Mammoth-Kill Site in southern Arizona, near the San Pedro River, preserves major evidence of Paleo-Indian hunting and camp activity from roughly 11,000 to 12,000 years ago. Excavations begun after Ed Lehner’s discoveries in the 1950s uncovered mammoth remains, hearths, fluted Clovis projectile points, and stone butchering tools found directly with animal bones. The site also yielded remains of bison, horse, tapir, camel, bear, rabbits, a garter snake, and a juvenile American mastodon, offering an unusually broad picture of the ancient environment. It became especially important for providing the first clearly defined Clovis hearths and the first radiocarbon dates for that culture.