| Rhondda to Caguas (Puerto Rico) | 4,069.96 mi (6,549.96 km) |
| Rhondda to Cahokia (Illinois) | 4,071.65 mi (6,552.69 km) |
| Rhondda to Calabasas (California) | 5,337.66 mi (8,590.13 km) |
| Rhondda to Caldwell (Idaho) | 4,744.76 mi (7,635.96 km) |
| Rhondda to Caledonia (Wisconsin) | 3,785.64 mi (6,092.40 km) |
| Rhondda to Calera (Alabama) | 4,196.67 mi (6,753.89 km) |
| Rhondda to Calexico (California) | 5,312.35 mi (8,549.40 km) |
| Rhondda to Calhoun (Georgia) | 4,056.59 mi (6,528.44 km) |
| Rhondda to California (Maryland) | 3,532.33 mi (5,684.73 km) |
| Rhondda to California City (California) | 5,253.96 mi (8,455.43 km) |
| Rhondda to Callaway (Florida) | 4,294.97 mi (6,912.09 km) |
| Rhondda to Calumet City (Illinois) | 3,826.92 mi (6,158.84 km) |
| Rhondda to Calverton (Maryland) | 3,517.21 mi (5,660.40 km) |
| Rhondda to Camano (Washington) | 4,661.62 mi (7,502.15 km) |
| Rhondda to Camarillo (California) | 5,344.76 mi (8,601.55 km) |
