Serpent Mound is the largest serpent effigy in the world, 1, 370 ft, varying in height from 1 to 3 ft. Based on the use of carbon dating and evidence from 1996 studies, many scholars believe that members of the Fort Ancient culture built it about 1070 CE (plus or minus 70 years). http://www.serpentmound.org/http://arcofappalachia.org/visit/serpent-mound.htmlhttp://www.greatserpentmound.com/
Mound City Group, Chillicothe, Ohio, is a large Hopewell culture (100 BC -- AD 500) ceremonial center located along the Scioto River in Ross County. It consists of 24 burial mounds framed by a large earthen enclosure shaped like a square with rounded corners. The enclosure is 2,050 feet across and the walls are about three feet high. http://www.ohiohistorycentral.org/entry.php?rec=2755http://www.nps.gov/hocu/index.htm
It rained most of the day and I was not able to take many photos.