The first Europeans to arrive in the Ohio Valley were intrigued and puzzled by the many conical earthen mounds they encountered there. They created wild theories about who the mysterious mound builders might be.It was not until the 1880s that Smithsonian Institution investigations revealed that the mound builders were the ancestors of living Native Americans. More than four hundred mounds have been recorded in West Virginia, including the Grave Creek Mound in Marshall County, once the largest conical mound in North America. Join archaeologist Darla Spencer and learn about the Grave Creek Mound and sixteen additional Adena mounds and groups of mounds from the fascinating Woodland period in West Virginia.