| Castlebar to Bougival | 601.06 mi (967.31 km) |
| Castlebar to Bouguenais | 571.13 mi (919.14 km) |
| Castlebar to Boulogne-Billancourt | 605.93 mi (975.15 km) |
| Castlebar to Boulogne-sur-Mer | 508.80 mi (818.83 km) |
| Castlebar to Bourg-de-Peage | 884.08 mi (1,422.80 km) |
| Castlebar to Bourg-en-Bresse | 831.21 mi (1,337.70 km) |
| Castlebar to Bourg-la-Reine | 610.98 mi (983.28 km) |
| Castlebar to Bourg-les-Valence | 883.83 mi (1,422.38 km) |
| Castlebar to Bourges | 693.90 mi (1,116.72 km) |
| Castlebar to Bourgoin-Jallieu | 863.37 mi (1,389.46 km) |
| Castlebar to Bressuire | 620.48 mi (998.56 km) |
| Castlebar to Brest | 431.47 mi (694.38 km) |
| Castlebar to Bretigny-sur-Orge | 618.11 mi (994.75 km) |
| Castlebar to Breuillet | 615.47 mi (990.50 km) |
| Castlebar to Briancon | 943.51 mi (1,518.43 km) |
