Ohio - Area of significance: Engineering
| Adams Covered Bridge |
| Ashtabula Harbor Light |
| Ballard Road Covered Bridge |
| Barkhurst Mill Covered Bridge |
| Barnesville Historic District |
| Bay View Hospital |
| Beginning Point of the U.S. Public Land Survey |
| Bell Covered Bridge |
| Belle Hall Covered Bridge |
| Bennett Schoolhouse Road Covered Bridge |
| Bergstresser Covered Bridge |
| Black River Viaduct, Baltimore And Ohio Railroad |
| Blackwood Covered Bridge |
| "Blaine Hill ""S"" Bridge" |
| B & O Railroad Viaduct |
| Bowman Mill Covered Bridge |
| Bright, John, Covered Bridge |
| Broadway Bridge |
| Brubaker Covered Bridge |
| Buckeye Furnace Covered Bridge |
| Byer Covered Bridge |
| Caledonia Bowstring Bridge |
| Cascade Locks Historic District |
| Cedar Point Light |
| Chambers Road Covered Bridge |
| Christman Covered Bridge |
| Chuckery Race |
| Church Hill Road Covered Bridge |
| Cincinnati and Whitewater Canal Tunnel |
| Cincinnati Street Gas Lamps |
| Cleveland And Pittsburgh Railroad Bridge |
| Cleveland Arcade |
| Cleveland Centre Historic District |
| Cleveland Warehouse District |
| Cleveland West Pierhead Light |
| Clinton Ohio and Erie Canal Historic District-Clinton Lock 2 and 3-Clinton Upper (Lock 2) and Clinton Lower (Lock 3) |
| Davidson, Tyler, Fountain |
| Dean Road Bridge |
| Deeds' Barn |
| Detroit Avenue Bridge |
| Detroit-Superior High Level Bridge |
| Dey Road Bridge |
| Division Avenue Pumping Station |
| DONALD B (towboat) |
| Dresden Suspension Bridge |
| Eagle Creek Covered Bridge |
| Eakin Mill Covered Bridge |
| East Ohio Building, The |
| Eldean Covered Bridge |
| Engineers Club of Dayton |
| Fairport Marine Museum |
| Falls River Road |
| First Concrete Street In U.S. |
| First National Bank Tower |
| Ford Motor Company Cincinnati Plant |
| Foreaker Bridge |
| Furnace Run Aqueduct |
| Gaston's Mill-Lock No. 36, Sandy And Beaver Canal District |
| Geeting Covered Bridge |
| Gendron, Peter, House |
| General U.S. Grant Bridge |
| Goodyear Airdock |
| Grant, William H., House |
| Great American Racing Derby |
| Green Island Light |
| Harmar Historic District |
| Harpersfield Covered Bridge |
| Harra Covered Bridge |
| Harshaville Covered Bridge |
| Harshman Covered Bridge |
| Hawthorn Hill |
| Helmick Covered Bridge |
| Helmick Mill Covered Bridge |
| Hercules Motors Corporation Industrial Complex |
| Hessler Court Wooden Pavement |
| Hildreth Covered Bridge |
| Hill, Jediah, Covered Bridge |
| Hizey Covered Bridge |
| Hobart Circle Historic District |
| Hobart, E. A., House |
| Hobart, William, Vacation House |
| Hocking Valley Railway Historic District |
| House at 1022 West Main Street |
| House at 121 South Ridge |
| House at 129 South Ridge |
| House at 145 South Ridge |
| House at 203 Penn Road |
| Huffman Covered Bridge |
| Huffman Field |
| Hune Covered Bridge |
| Ida Street Viaduct |
| Ingalls Building |
| Inter County Highway 360 |
| Interurban Bridge |
| John Bright No. 1 Iron Bridge |
| Johnson Road Covered Bridge |
| Kettering, Charles F., House |
| Kidwell Covered Bridge |
| Kirby, James, Mill |
| Kirker Covered Bridge |
Data from United States Park Service and Wikidata
