Region
Ohio
37
West Virginia
6
Pennsylvania
5
California
4
Kentucky
4
United States
3
Alaska
2
Belmont County
2
Chesapeake and Ohio Canal National Historical Park
2
Cleveland
2
Idaho
2
Indiana
2
Montana
2
Ohio River Valley
2
Oklahoma
2
Portage County
2
Texas
2
Alabama
1
Anderson County
1
Antietam National Battlefield
1
Antietam National Battlefield (Md.)
1
Appalachian Basin
1
Austin County
1
Beaverhead County
1
Carter County
1
Colorado
1
Creek County
1
Cuyahoga County
1
Dayton Region
1
Estill County
1
Greene County
1
Harpers Ferry National Historical Park
1
Hopewell Culture National Historical Park
1
Hopewell Culture National Historical Park (Ohio)
1
Illinois
1
Kansas
1
Klamath Mountains (Calif. and Or.)
1
Lake City Quadrangle
1
Louisiana
1
Maryland
1
Miami County
1
Miami River Valley
1
Montgomery County
1
Nebraska
1
Nevada
1
North America
1
Oregon
1
Potomac River Valley
1
Santa Barbara County
1
South Dakota
1
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