| Ottawa to Rockville (Maryland) | 634.87 mi (1,021.73 km) |
| Ottawa to Rockville Centre (New York) | 792.28 mi (1,275.05 km) |
| Ottawa to Rockwall (Texas) | 717.46 mi (1,154.64 km) |
| Ottawa to Rocky Mount (North Carolina) | 700.69 mi (1,127.65 km) |
| Ottawa to Rocky Point (New York) | 826.09 mi (1,329.47 km) |
| Ottawa to Rocky River (Ohio) | 361.34 mi (581.53 km) |
| Ottawa to Roessleville (New York) | 775.90 mi (1,248.69 km) |
| Ottawa to Rogers (Arkansas) | 450.79 mi (725.47 km) |
| Ottawa to Rogers (Minnesota) | 356.55 mi (573.81 km) |
| Ottawa to Rohnert Park (California) | 1,797.07 mi (2,892.10 km) |
| Ottawa to Rolla (Missouri) | 282.57 mi (454.75 km) |
| Ottawa to Rolling Meadows (Illinois) | 64.62 mi (103.99 km) |
| Ottawa to Roma (Texas) | 1,183.84 mi (1,905.21 km) |
| Ottawa to Rome (Georgia) | 528.45 mi (850.45 km) |
| Ottawa to Rome (New York) | 692.93 mi (1,115.17 km) |
