Evidence of man in Ohio goes back as far as 13,000 BC, with the first inhabitants after the last ice age most likely being Paleo-Indians who seemed to have disappeared after the Younger Days impact event . Later they were replaced by Archaic people who are refered to as Native Americans. The Archaic period has been seen as divided into Early, Middle and Late Archaic periods, it is thought of as the second (possibly) period of human occupation that took place 8,000 BC to 1,000 BC.. The Woodlands Period went from about 1,000 BC to 700 AD and included the Adena and Hopewell peoples who are sometimes referred to as the Mound Builders. Other cultures extended the Mound Builders period to about 1300 AD.
Teotihuacan construction dates back to about 200BC to 100 AD.
Hopewell Culture National Historical Park, 16062 State Route 104, Chillicothe, Ohio 45601. [] 200 BC to AD 500.
Adena Conical Burial Mound. AKA Campbell Mound State Memorial. 20 feet high - 100 feet in diameter. Close to 270 W and I 70 intersection in Columbus OH on Montgomery St. Woodlands Period about 1,000 BC - 700 AD.
The Pyramids at Marietta [] at Marietta OH. Little definative information.
Moundbuilders Earthworks []This site covers most of Newark, Ohio. Two main areas have been preserved. One area is at the park where you will find an embankment that is 1,200 feet in diameter with earthen walls from 8 to 14 feet hign enclosing a 26 acre area. The other more impressive site (Octagon Earthworks) has a golf course located in it with some efforts of preservation, there is an observation stand. Hopewell Indians (100 BC-AD 500)
Wright Earthworks, Newark OH  Wright Earthworks, located less than a block west of the SR 79 intersection at Grant St.in Newark, Licking County, Ohio. The earthwork remnants may be viewed from James Street, a short distance from Grant Street and the SR 79 interchange. Hopewell Indians (100 BC-AD 500}(
Serpant Mound State Memorial, Peebles (Ohio), [] OH. A serpentine effigy mound built by Adena Indians, approx. 20 feet wide and nearly 0.25 miles long. The effigy represents an uncoiling serpant. Quite an impressive sight. The museum houses artifacts, pottery, implements and models depicting the construction of the Mound. Adena (800 BC-AD 100)
SunWatch Indian Village/Archaeological Park, 2301 West River Road, Dayton , Ohio[]. 800-year-old village built by the Fort Ancient Indians.
Flint Ridge State Memorial3 miles south of Cynthia (Ohio), near (souh/east) Newark (Ohio) off of SR 668. [] Flint Ridge is a restored prehistoric quarry pit with a museum that explains both the digging and shaping of flint. It is a site well worth the visit. There is a knap-in (teaching, exhibiting knapping, swap flint) every Labor Day week end. At the other end of the park there is a camping area that has a fossil swap the same week end.