| Boulder to Rosemont (California) | 865.97 mi (1,393.64 km) |
| Boulder to Rosemount (Minnesota) | 701.27 mi (1,128.59 km) |
| Boulder to Rosenberg (Texas) | 899.12 mi (1,447.00 km) |
| Boulder to Roseville (California) | 861.05 mi (1,385.73 km) |
| Boulder to Roseville (Michigan) | 1,168.09 mi (1,879.86 km) |
| Boulder to Roseville (Minnesota) | 704.96 mi (1,134.52 km) |
| Boulder to Rossmoor (California) | 828.15 mi (1,332.78 km) |
| Boulder to Rossville (Maryland) | 1,523.95 mi (2,452.56 km) |
| Boulder to Roswell (Georgia) | 1,221.24 mi (1,965.40 km) |
| Boulder to Roswell (New Mexico) | 461.33 mi (742.44 km) |
| Boulder to Round Lake (Illinois) | 904.26 mi (1,455.27 km) |
| Boulder to Round Lake Beach (Illinois) | 905.72 mi (1,457.61 km) |
| Boulder to Round Rock (Texas) | 782.76 mi (1,259.72 km) |
| Boulder to Rowland Heights (California) | 812.03 mi (1,306.83 km) |
| Boulder to Rowlett (Texas) | 688.61 mi (1,108.22 km) |
