Ohio - Criteria: A (event)
| Greenwood Cemetery |
| Gregory House |
| Griggs Grange No. 1467 |
| Griswold Memorial Young Women's Christian Association |
| Gross, L.N., Company Building |
| Grossman Paper Box Company |
| Groveport Log Houses |
| Groveport School |
| Groveport Town Hall Historic Group |
| Gruenwald Convent |
| Gruen Watch Company-Time Hill |
| Gwinn Estate |
| Haddon Hall |
| Haines House |
| Halle Building |
| Halle's Shaker Square |
| Hamilton Catholic High School |
| Hamilton County Memorial Building |
| Hamilton Historic Civic Center |
| Hamilton, J. L., Residence |
| Hamilton Park Historic District |
| Hanford Village George Washington Carver Addition Historic District |
| Hanna, Leonard C., Jr., Estate |
| Hardin County Courthouse |
| Harding-Jones Paper Company District |
| Harmar Historic District |
| Harmony Hill Dairy House |
| Harper-Cosgrave Block |
| Harper, Rice, House |
| Harra Covered Bridge |
| Harris, Dr. John, Dental School |
| Harrison National Bank |
| Harris, William B., House |
| Harshaville Covered Bridge |
| Harshman Covered Bridge |
| Hartman Hotel |
| Hart's Drug Store |
| Hartville Hotel |
| Harvard Company-Weber Dental Manufacturing Company |
| Harvey, Eli, House |
| Harvey One-Room School |
| Harwood Block |
| Hayden Building |
| Haydenville Historic Town |
| Hayesville Opera House |
| Hay-McKinney and Bingham-Hanna House |
| Headley Inn., Smith House And Farm |
| Hedges-Hunter-Keller-Bacon Gristmill |
| Helen Chapel |
| Henninger, Phillip, House |
| Henry County Courthouse |
| Henry County Sheriff's Residence and Jail |
| Herrington, John, House and Herrington Bethel Church |
| Herron Gymnasium |
| Hertzler, Daniel, House |
| Heter Farm |
| Heyne-Zimmerman House |
| High and Gay Streets Historic District |
| Highland County Courthouse |
| High Street Commercial Block |
| Hildreth Covered Bridge |
| Hill, Jediah, Covered Bridge |
| Hinde & Dauch Paper Co. |
| Hinde & Dauch Paper Co. |
| Hinde & Dauch Paper Co. |
| Hine, Horace L., House |
| Hirons-Brown House |
| Hise, Daniel Howell, House |
| Historic Associate Reformed Church and Cemetery |
| Hizey Covered Bridge |
| Hobart, E. A., House |
| Hocking Valley Railway Historic District |
| Holy Cross Church, Rectory and School |
| Holy Cross Lithuanian Roman Catholic Church |
| Holy Cross Monastery and Chapel |
| Holy Family Catholic Church |
| Holy Rosary Church |
| Home for the Aged Deaf |
| Honam, John, House |
| Hoover Farm |
| Hope Furnace |
| Hostetter Inn |
| Hotel Ashtabula |
| Hotel Central |
| Hotel Metropole |
| Hotel Rieger |
| Hotel Statler |
| 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 |
| House at 753 East Broad Street |
| Howe Tavern |
| Hruby Conservatory of Music |
| Hudson Historic District |
| Huffman Field |
| Hull, Patrick, House |
| Hune Covered Bridge |
| Hune, William, Farm |
Data from United States Park Service and Wikidata
