Ohio - Significance region: Local
| Renick House, Paint Hill |
| Renkert, Harry S., House |
| Renner, George J., Jr., House |
| Rennert Mound Archeological District |
| Rentschler House |
| Renz Block |
| Resor, William, House |
| Retszch, W. C., House |
| Reynolds, John R., House |
| Rhoads, Peter F., House |
| Rhodes and Watters Apartment Buildings, The |
| Richard, John, Residence |
| Richards-Sewall House |
| Rich, Charles B., House |
| Richey, James, Farmhouse |
| Richland County Infirmary |
| Richland Trust Building |
| Richman Brothers Company, The |
| Rich, N.J., and Co. Building |
| Riddle Block |
| Riddle Block #11 |
| Riddle Block #5 |
| Riddle Block #9 |
| Riddle-Friend House |
| Rider, Adam, House |
| Ridgewood Historic District |
| Riley, F., House |
| Riley Specialty Shoe Company |
| Rinderknecht, Christian H., House |
| Rinehart, Hugh T., House |
| Rings, Louis, Barn #1 |
| Rings, Louis, Barn #2 |
| Rings, Louis, Residence |
| Ring, Walter, House and Mill Site |
| Ripley House |
| Risingsun Town Hall and Opera House |
| Ritter, William, House |
| Riverside Cemetery Building |
| Riverside Cemetery Chapel |
| Riverside Chapel |
| Riverview |
| Riverview Apartments |
| Riverview House Apartments |
| Roach, Moses and Minerva, House |
| Roas-Ilhardt Farm and Winery |
| Robb, L. B., Drugstore |
| Roberts Mound |
| Robeson, Dr. Donovan, House |
| Robinson Building |
| Robinson, Byron W., House |
| Robinson, Edmund, House |
| Robinson-Pavey House |
| Rochester Square Historic District |
| Rock Creek School |
| Rockefeller Building |
| Rock Hill Presbyterian Church |
| Rock Hollow School |
| Rock Mill |
| Rocky Fork Park Group |
| Rocky Fork Park Site |
| Rohr, David, Mansion And Carriage House |
| Root, A. I. And E. R., Homestead |
| Root Covered Bridge |
| Root, Joseph, House |
| Root, William H., House |
| Ropes, Nathaniel, Building |
| Rose, D. S., Mound |
| Rose Hill and Community House |
| Roseville High School |
| Ross, Edith, Mound |
| Ross-Gowdy House |
| Ross Hardware |
| Roudebush Farm |
| Round Barn |
| Round Barn |
| Round Barn |
| Round Hill |
| Roundwood Manor at Daisy Hill Farm |
| Royalton House |
| Ruggles, Charles, House |
| Rushville Historic District |
| Russell, Mark, House |
| Sachs and Pruden Ale Company Building |
| Sacred Heart Academy |
| Sacred Heart Church |
| Sacred Heart of Jesus Churches |
| Sage House |
| Sail Loft |
| Saint Anne's Hill Historic District |
| Saint John the Evangelist Catholic Church Complex |
| Saint Joseph's Catholic Church |
| Saint Joseph's Roman Catholic Church |
| Saint Mary's Episcopal Church and Parish House |
| Saint Peter and Saint Paul Historic District-Oliver's Second addition |
| Saint Philip's Episcopal Church |
| Salem Bear Creek Church, Salem Evangelical Lutheran Church |
| Salem Church |
| Salem Downtown Historic District |
| Salem Methodist Church Complex |
| Salem Methodist Episcopal Church |
Data from United States Park Service and Wikidata
