| Cwmbran to Olympia Heights (Florida) | 4,312.25 mi (6,939.89 km) |
| Cwmbran to Omaha (Nebraska) | 4,179.49 mi (6,726.24 km) |
| Cwmbran to On Top of the World Designated Place (Florida) | 4,225.35 mi (6,800.05 km) |
| Cwmbran to Onalaska (Wisconsin) | 3,875.65 mi (6,237.25 km) |
| Cwmbran to Oneida (New York) | 3,307.33 mi (5,322.63 km) |
| Cwmbran to Oneonta (New York) | 3,309.19 mi (5,325.63 km) |
| Cwmbran to Ontario (California) | 5,319.56 mi (8,561.00 km) |
| Cwmbran to Ontario (Oregon) | 4,743.83 mi (7,634.46 km) |
| Cwmbran to Opa-locka (Florida) | 4,299.83 mi (6,919.90 km) |
| Cwmbran to Opelika (Alabama) | 4,178.78 mi (6,725.09 km) |
| Cwmbran to Opelousas (Louisiana) | 4,558.56 mi (7,336.30 km) |
| Cwmbran to Orange (California) | 5,339.97 mi (8,593.86 km) |
| Cwmbran to Orange (Texas) | 4,646.75 mi (7,478.22 km) |
| Cwmbran to Orange City (Florida) | 4,191.82 mi (6,746.09 km) |
| Cwmbran to Orangeburg (South Carolina) | 3,952.09 mi (6,360.28 km) |
