From Ohio History Central
The Buffington Island Mound is a large, conical burial mound located along the Ohio River in Meigs County, Ohio. It is typical of mounds known to have been built by the Adena Culture (circa 800 BC-AD 100), but the cultural affiliation is not known for certain. The mound is 20 feet high and 125 feet in diameter at the base.
Although it was dug into at some point during the early 19th century, no report of what was found is known to exist. The mound was restored in 1931. Currently, it is part of Buffington Island State Memorial.