| Ottawa to Romeoville (Illinois) | 42.16 mi (67.85 km) |
| Ottawa to Romulus (Michigan) | 287.55 mi (462.77 km) |
| Ottawa to Ronkonkoma (New York) | 817.54 mi (1,315.71 km) |
| Ottawa to Roosevelt (New York) | 794.95 mi (1,279.35 km) |
| Ottawa to Rosamond (California) | 1,650.58 mi (2,656.35 km) |
| Ottawa to Rosaryville (Maryland) | 658.64 mi (1,059.98 km) |
| Ottawa to Roscoe (Illinois) | 74.53 mi (119.94 km) |
| Ottawa to Rose Hill (Virginia) | 643.87 mi (1,036.21 km) |
| Ottawa to Roseburg (Oregon) | 1,756.86 mi (2,827.40 km) |
| Ottawa to Rosedale (California) | 1,687.08 mi (2,715.09 km) |
| Ottawa to Rosedale (Maryland) | 663.05 mi (1,067.07 km) |
| Ottawa to Roselle (Illinois) | 57.67 mi (92.81 km) |
| Ottawa to Roselle (New Jersey) | 760.17 mi (1,223.37 km) |
| Ottawa to Roselle Park (New Jersey) | 759.69 mi (1,222.61 km) |
| Ottawa to Rosemead (California) | 1,667.32 mi (2,683.29 km) |
