The Oscar Leibhart Site, designated (36YO9) is a historic archaeological site located at Lower Windsor Township, York County, Pennsylvania. It was the site of a prehistoric and protohistoric village. The site was first discovered by 1910, with more extensive digging between 1925 and 1936. In 1956, the Pennsylvania State Museum undertook an excavation of a longhouse and grave sites. Another excavation took place in August 1975. Artifacts uncovered from the site date to the Early Woodland Period (1000 B.C. - 200 B.C.) and late-17th century.