The prehistoric Bens Run earthworks were located on a terrace of the Ohio River between the present communities of Bens Run and Long Reach, in Tyler County. The earliest eyewitness account of the earthworks was from the 1808 journal of Lewis Summers, who described it as "an ancient encampment" with square trenches enclosing an area of ten acres. In 1818, the journal of Thom Nuttall described the earthworks as "a small square embankment containing near an acre, with only one or two openings or entrances."

Later accounts described an oval or rectangular area of approximately 400 acres enclosed by the remnants of two parallel walls of earth and stone, six to 12 feet high and 120 feet apart, approximately four miles in length. A cross wall was reported running from one long side of the enclosure to the other, with two additional interior walls extending south from the cross wall. Two earthen mounds were reported within the enclosure, and several more mounds were located nearby.

The Archeology Section of the West Virginia Geological and Economic Survey officially recorded the Bens Run earthworks in 1965. By that time, all visible remnants of the earthworks were gone, probably through repeated plowing, although one of the mounds remained. Archeological surveys conducted in the 1990s found no evidence of the enclosure. While it seems likely that there were earthworks at Bens Run, the true dimensions may never be known. The discrepancies in the accounts may be the result of embellishment and secondhand reports. Data for similar enclosures recorded in West Virginia and Ohio support the earlier, more conservative descriptions.