Portland

Historical marker location:

53969 Co Hwy 31, Portland, Ohio

( Marker is on Bald Knob-Stiversville Road (County Road 31) 0.2 miles west of Ohio River Scenic Byway (State Route 124), on the right when traveling east.)

Marker installed: 2013

Edge of the Woods. John Hunt Morgan Heritage Trail.

The Great Serpent Mound, located in Adams County, Ohio, is a prehistoric effigy mound in the shape of a serpent that is more than 1,300 feet long. It is one of the largest effigy mounds in the world and is estimated to have been built by the Adena culture more than 1,000 years ago.