| Boulogne-sur-Mer to Cervello | 644.86 mi (1,037.81 km) |
| Boulogne-sur-Mer to Cervera | 626.25 mi (1,007.85 km) |
| Boulogne-sur-Mer to Ceuti | 885.22 mi (1,424.62 km) |
| Boulogne-sur-Mer to Cheste | 785.01 mi (1,263.36 km) |
| Boulogne-sur-Mer to Chiclana de la Frontera | 1,060.93 mi (1,707.41 km) |
| Boulogne-sur-Mer to Chipiona | 1,045.50 mi (1,682.57 km) |
| Boulogne-sur-Mer to Chiva | 785.83 mi (1,264.67 km) |
| Boulogne-sur-Mer to Churriana de la Vega | 973.28 mi (1,566.35 km) |
| Boulogne-sur-Mer to Ciempozuelos | 772.44 mi (1,243.12 km) |
| Boulogne-sur-Mer to Cieza | 875.45 mi (1,408.90 km) |
| Boulogne-sur-Mer to Cisterniga | 697.22 mi (1,122.06 km) |
| Boulogne-sur-Mer to Ciudad de Melilla | 1,091.15 mi (1,756.03 km) |
| Boulogne-sur-Mer to Ciudad Real | 854.79 mi (1,375.66 km) |
| Boulogne-sur-Mer to Ciudad-Rodrigo | 801.91 mi (1,290.55 km) |
| Boulogne-sur-Mer to Cocentaina | 833.87 mi (1,341.98 km) |
