| Castlebar to Berga | 959.75 mi (1,544.57 km) |
| Castlebar to Berja | 1,214.24 mi (1,954.13 km) |
| Castlebar to Bermeo | 780.49 mi (1,256.08 km) |
| Castlebar to Berriozar | 837.25 mi (1,347.43 km) |
| Castlebar to Betanzos | 732.79 mi (1,179.30 km) |
| Castlebar to Betera | 1,069.07 mi (1,720.50 km) |
| Castlebar to Bilbao | 787.75 mi (1,267.76 km) |
| Castlebar to Binefar | 939.72 mi (1,512.33 km) |
| Castlebar to Binisalem | 1,131.87 mi (1,821.56 km) |
| Castlebar to Blanes | 1,009.02 mi (1,623.87 km) |
| Castlebar to Boadilla del Monte | 963.19 mi (1,550.10 km) |
| Castlebar to Boiro | 774.81 mi (1,246.93 km) |
| Castlebar to Bolanos de Calatrava | 1,067.70 mi (1,718.29 km) |
| Castlebar to Bollullos de la Mitacion | 1,151.85 mi (1,853.73 km) |
| Castlebar to Bollullos par del Condado | 1,149.33 mi (1,849.66 km) |
