| Boulder to Cernavoda | 5,925.39 mi (9,536.00 km) |
| Boulder to Chitila | 5,858.15 mi (9,427.78 km) |
| Boulder to Cisnadie | 5,738.36 mi (9,235.00 km) |
| Boulder to Cluj-Napoca | 5,663.82 mi (9,115.03 km) |
| Boulder to Codlea | 5,776.07 mi (9,295.69 km) |
| Boulder to Comanesti | 5,762.79 mi (9,274.32 km) |
| Boulder to Comarnic | 5,806.50 mi (9,344.66 km) |
| Boulder to Constanta | 5,951.74 mi (9,578.40 km) |
| Boulder to Corabia | 5,856.46 mi (9,425.06 km) |
| Boulder to Costesti | 5,817.46 mi (9,362.30 km) |
| Boulder to Covasna | 5,788.26 mi (9,315.31 km) |
| Boulder to Craiova | 5,805.09 mi (9,342.39 km) |
| Boulder to Cristuru Secuiesc | 5,731.28 mi (9,223.61 km) |
| Boulder to Cugir | 5,708.38 mi (9,186.75 km) |
| Boulder to Cumpana | 5,952.71 mi (9,579.97 km) |
