The Backusburg Mounds (15-CW-64) are an archaeological site in the Jackson Purchase region of the U.S. state of Kentucky. Located near the tiny community of Backusburg in northwestern Calloway County, the mounds are one of the region's premier archaeological sites. Since at least the early years of the twentieth century, the mounds have been well known locally, due partially to their large size; the largest mound measures 150 by 75 feet (46 m × 23 m) at the base. Located on a ridgeline above a fork of the Clarks River, the mound bears a peculiar shape; its size and shape have caused observers to suggest that it might actually be the remnants of a series of smaller mounds placed next to each other. As late as the 1930s, this largest mound had never been plowed; it lay in dense woodland, and