Grave Creek Mound

At 62 feet (19 m) high and 240 feet (73 m) in diameter, the Grave Creek Mound in the Ohio River Valley in West Virginia is one of the largest conical-type burial mounds in the United States. The builders of the site, members of the Adena culture, moved more than 60,000 tons of dirt to create it about 250–150 BC. The earthwork mound is located in present-day Moundsville near the banks of the Ohio River.

• http://en.wikipedia.org/wiki/Grave Creek Mound