The Octagon Earthworks are part of the Newark Earthworks complex of prehistoric Indian earthworks, originally one of the most extensive earthworks of its kind in the country.

Enclosing 50 acres, the Octagon Earthworks are joined by parallel walls to a circular embankment enclosing 20 acres. Within the octagon, opposite the openings are small mounds. The Octagon Earthworks were built by the Hopewell Indians (100 BC-AD 500) and were probably used for ceremonial, social, and religious purposes. Wright Earthworks and The Great Circle Earthworks (formerly known as Moundbuilders State Memorial) are both additional local sites that preserve other features of this majestic remnant of Prehistoric Ohio.

At present the Octagon Earthworks are on the Moundbuilders Country Club golf course. Use care in viewing them.