| Rhondda to Oakley (California) | 5,215.26 mi (8,393.15 km) |
| Rhondda to Oakton (Virginia) | 3,539.24 mi (5,695.85 km) |
| Rhondda to Oakville (Missouri) | 4,082.74 mi (6,570.53 km) |
| Rhondda to Oatfield (Oregon) | 4,820.79 mi (7,758.30 km) |
| Rhondda to Ocala (Florida) | 4,199.91 mi (6,759.10 km) |
| Rhondda to Ocean Acres (New Jersey) | 3,377.06 mi (5,434.85 km) |
| Rhondda to Ocean City (New Jersey) | 3,411.04 mi (5,489.54 km) |
| Rhondda to Ocean Pines (Maryland) | 3,472.60 mi (5,588.60 km) |
| Rhondda to Ocean Pointe (Hawaii) | 7,168.35 mi (11,536.34 km) |
| Rhondda to Ocean Springs (Mississippi) | 4,414.80 mi (7,104.93 km) |
| Rhondda to Oceanside (California) | 5,343.80 mi (8,600.02 km) |
| Rhondda to Oceanside (New York) | 3,312.19 mi (5,330.46 km) |
| Rhondda to Ocoee (Florida) | 4,203.52 mi (6,764.91 km) |
| Rhondda to Oconomowoc (Wisconsin) | 3,795.68 mi (6,108.56 km) |
| Rhondda to Odenton (Maryland) | 3,506.34 mi (5,642.91 km) |
