| Ashland |
| Clear Fork Gorge State Nature Preserve |
| Mohican Memorial State Forest |
| Mohican State Park |
|
| Ashtabula |
| Benetka Road Covered Bridge |
| Caine Road Covered Bridge |
| Conneaut Harbor Preserve |
| Creek Road Covered Bridge |
| Doyle Road Covered Bridge |
| Geneva State Park |
| Giddings Road Covered Bridge |
| Graham Road Covered Bridge |
| Harpersfield Road Covered Bridge |
| Mechanicsville Road Covered Bridge |
| Middle Road Covered Bridge |
| Netcher Road Covered Bridge |
| Olins Road Covered Bridge |
| Pymatuning Lake Wildlife Area |
| Pymatuning State Park |
| Riverdale Road Covered Bridge |
| Root Road Covered Bridge |
| South Denmark Road Covered Bridge |
| State Road Covered Bridge |
| Warner Hollow Road Covered Bridge |
|
| Carroll |
| Atwood Lake Wildlife Area |
| Blue Bird Farm Covered Bridge |
|
| Columbiana |
| Beaver Creek State Forest |
| Beaver Creek State Park |
| Church Hill Road Covered Bridge |
| Guilford State Park |
| Highlandtown Lake Wildlife Area |
| McClellan Covered Bridge |
| Sells Covered Bridge |
| Sheepskin Hollow State Nature Preserve |
| Teegarden Covered Bridge |
| Thomas Malon Covered Bridge |
| Yellow Creek State Forest |
|
| Coshocton |
| Helmick Covered Bridge |
| Woodbury State Wildlife Area |
|
| Cuyahoga |
| Charles Harding Memorial Covered Bridge |
| Cleveland Lakefront State Park & Wildlife Area |
| Cleveland Museum of Natural History |
| Cuyahoga Valley National Park |
| Shaker Lakes Regional Nature Center |
| Tinker's Creek Gorge |
|
|
| Erie |
| DuPont Marsh Preserve |
| Erie Sand Barrens State Nature Preserve |
| Glacial Grooves State Memorial |
| Kelley's Island State Park |
| Milan State Wildlife Area |
| North Pond State Nature Preserve |
| North Shore Alvar |
| Old Woman Creek State Nature Preserve & Estuarine Research
Reserve |
| Sheldon Marsh State Nature Preserve |
| The Blue Hole at Castalia |
|
| Geauga |
| Aquilia Lake State Wildlife Area |
| Big Creek Park |
| Burton Wetlands |
| Metals Park |
| Punderson State Park |
| Thompson Ledge Park |
|
| Harrison |
| Harrison State Forest |
| History of Coal Museum |
| Skull Fork Covered Bridge |
|
| Huron |
| National Champion Big Tree: Ohio Buckeye |
| Olsen, Augusta-Anne State Nature Preserve |
|
| Jefferson |
| Brush Creek Wildlife Area |
| Fernwood State Forest |
| Jefferson Lake State Park |
|
| Knox |
| Brinkhaven Access Wildlife Preserve |
| Knox Woods State Nature Preserve |
| National Champion Big Tree: Norway Maple |
|
| Lake |
| Chapin Forest Reservation |
| Hach-Otis State Nature Preserve |
| Headlands Beach State Park |
| Headlands Dunes State Nature Preserve |
| Hogback Ridge Park Archaeology & Historical Site |
| Holden Arboretum (Private) |
| Indian Point Park Archaeology Site |
| Mentor Marsh State Nature Preserve |
| National Champion Big Tree: Kentucky Coffeetree |
|
| Lorain |
| Black River Reservation |
| Findley State Park |
| Indian Hollow Reservation |
| Vermilion River Reservation |
|
| Mahoning |
| Kyle (Arthur) Woods State Nature Preserve |
| Lake Milton State Park |
| Mill Creek Park |
|
| Medina |
| Hinckley Reservation Scenic Area |
| Spencer Lake Wildlife Area |
| Swamp Cottonwood |
|
| Portage |
| Aurora Sanctuary |
| Blanche Katherine Novak Nature Preserve |
| Eagle Creek State Nature Preserve |
| Frame Lake Fen |
| Kent/Cooperrider Bog |
| Lake Milton Wildlife Area |
| Mogadore Reservoir Wildlife |
| Nelson Kennedy Ledges State Park |
| Tinker's Creek State Nature Preserve |
| Tinker's Creek State Park |
| Tummonds (Charles A) River Preserve |
| West Branch State Park |
|
| Richland |
| Fowler Woods State Nature Preserve |
| Hemlock Falls |
| Malabar Farm State Park |
| Mohican State Park |
| Pleasant Hill Lake Wildlife |
|
| Stark |
| Dale Walborn Reservoir Wildlife Area |
| Jackson Bog State Nature Preserve |
| McKinley Museum of Science and Technology |
| National Champion Big Tree: Cucumbertree Magnolia |
| Quail Hollow State Park |
|
| Summit |
| Adell Durban Park and Arboretum |
| Deep Lock Quarry |
| Everett Covered Bridge |
| Furnace Run |
| Gorge Metropark |
| Hale Farm and Village |
| North Reservoir Wildlife Area |
| Portage Lakes State Park |
| Portage Lakes Wetland |
|
| Trumbull |
| Grand River Wildlife Area |
| Mosquito Creek Wildlife Area |
| Mosquito Lake State Park |
| Newton Falls Covered Bridge |
|
| Tuscarawas |
| Devil's Den Park |
| Zoar Lake |
|
| Wayne |
| Brown's Lake Bog State Nature Preserve |
| Johnson Woods State Nature Preserve |
| Ken Miller's Oil
& Gas Museum |
| Shreve Lake Wildlife Area |
|
