Map of Adena Hopewell Mounds and Earthworks in Ohio

 222 Burial Mound and Earthworks Sites in Ohio, Indiana, Kentucky, West Virginia and Michigan. 

Earthworks found around Chillicothe, Ohio.  None of the earthworks were preserved, with the few that did survive until the 20th century being destroyed by the Ohio Historical Society.  Map from Ancient Monuments of the Mississippi Valley, 1848.
Chillicothe, Ohio (Ross County) Mounds and Earthworks Map
      Exhibiting a section of twelve miles of the Scioto valley, with its ancient monuments, will serve to give some general conception of the number of these remains. The enclosures are here indicated by dark lines, the mounds by simple dots. Within the section represented, it will be observed that there are not less than ten groups of large works, accompanied by a great number of mounds, of various sizes. Within the enclosure designated by the letter E are embraced twenty-four mounds. The enclosures D, H, I, K, have each about two and a half miles of embankment; and Hand K enclose but little less than one hundred acres each. It is proper to observe, to prevent misconception, that there are few sections of country of equal extent which embrace so large a number of ancient works. The fertile valley of the Scioto river was a favorite resort of the ancient people, and was one of the seats of their densest population. 

Earthworks located west of Chilliocthe, Ohio along Pant Creek.  Spuce Hill and the Seip mound and earthwork can still be explored.

Valley of Paint Creek Earthworks Map

    Enlarged planPLATE III, No. 1, exhibits a section of six miles of the Valley of Paint Creek, a tributary of the Scioto river. The village of Bourneville is ten miles west of Chillicothe. Within this limit are embraced three works of extraordinary size, besides several smaller ones. The works, designated by the letters A and B, have each upwards of two miles of heavy embankment, and contain not far from one hundred acres. The stone work C has an area of one hundred and forty acres, enclosed within a wall upwards of two and a fourth miles long

The Great Miami Valley Earthwork Map

PLATE III, No. 2, presents a section of six miles of the Great Miami valley, included principally within the limits of Butler county, Ohio. Not less than seven enclosures, of considerable size, occur within these bounds. The work indicated by the letter G contains ninety-five acres. 
Not far from one hundred enclosures of various sizes, and five hundred mounds, are found in Ross county, Ohio. The number of tumuli in the State may be safely estimated at ten thousand, and the number of enclosures at one thousand or fifteen hundred. Many of them are small, but cannot be omitted in an enumeration. They are scarcely less numerous on the Kenhawas in Virginia, than on the Scioto and Miamis; and are abundant on the White river and Wabash, as also upon the Kentucky, Cumberland, Tennessee, and the numerous other tributaries of the Ohio and Mississippi.
Nor is their magnitude less a matter of remark than their great number. Lines of embankment, varying in height from five to thirty feet, and enclosing areas of from one to fifty acres, are common; while enclosures of one or two hundred acres area are far from infrequent. Occasional works are found enclosing as many as four hundred acres3 The magnitude of the area enclosed is not, however, always a correct index of the amount of labor expended in the erection of these works. A fortified hill in Highland county, Ohio, has one mile and five-eighths of heavy embankment; yet it encloses an area of only about forty acres. A similar work on the Little Miami river, in Warren county, Ohio, has upwards of four miles of embankment, yet encloses little more than one hundred acres. The group of works at the mouth of the Scioto river has an aggregate of at least twenty miles of embankment; yet the entire amount of land embraced within the walls does not probably much exceed two hundred acres.
The mounds are of all dimensions, from those of but a few feet in height and a few yards in diameter, to those which, like the celebrated structure at the mouth of Grave Creek in Virginia, rise to the height of seventy feet, and measure one thousand feet in circumference at the base. The great mound in the vicinity of Miamisburgh, Montgomery county, Ohio, is sixty-eight feet in perpendicular height, and eight hundred and fifty-two in circumference at the base, containing 311,353 cubic feet.