| Rhondda to Cookeville (Tennessee) | 4,000.71 mi (6,438.51 km) |
| Rhondda to Coolidge (Arizona) | 5,159.84 mi (8,303.96 km) |
| Rhondda to Coon Rapids (Minnesota) | 3,880.65 mi (6,245.30 km) |
| Rhondda to Cooper City (Florida) | 4,277.24 mi (6,883.54 km) |
| Rhondda to Coos Bay (Oregon) | 4,982.36 mi (8,018.34 km) |
| Rhondda to Copiague (New York) | 3,300.50 mi (5,311.64 km) |
| Rhondda to Coppell (Texas) | 4,614.99 mi (7,427.11 km) |
| Rhondda to Copperas Cove (Texas) | 4,745.89 mi (7,637.78 km) |
| Rhondda to Coral Gables (Florida) | 4,293.86 mi (6,910.30 km) |
| Rhondda to Coral Springs (Florida) | 4,264.83 mi (6,863.57 km) |
| Rhondda to Coral Terrace (Florida) | 4,293.13 mi (6,909.13 km) |
| Rhondda to Coralville (Iowa) | 3,978.16 mi (6,402.22 km) |
| Rhondda to Coram (New York) | 3,275.61 mi (5,271.59 km) |
| Rhondda to Corcoran (California) | 5,256.62 mi (8,459.71 km) |
| Rhondda to Cordele (Georgia) | 4,131.08 mi (6,648.33 km) |
