| Boulder to Bollullos par del Condado | 5,021.41 mi (8,081.18 km) |
| Boulder to Bormujos | 5,040.53 mi (8,111.96 km) |
| Boulder to Brenes | 5,041.45 mi (8,113.42 km) |
| Boulder to Brunete | 4,999.90 mi (8,046.56 km) |
| Boulder to Bueu | 4,721.53 mi (7,598.57 km) |
| Boulder to Bullas | 5,198.57 mi (8,366.29 km) |
| Boulder to Bunol | 5,174.53 mi (8,327.60 km) |
| Boulder to Burela de Cabo | 4,725.60 mi (7,605.12 km) |
| Boulder to Burgos | 4,929.71 mi (7,933.60 km) |
| Boulder to Burjasot | 5,186.38 mi (8,346.68 km) |
| Boulder to Burriana | 5,182.15 mi (8,339.86 km) |
| Boulder to Cabanaquinta | 4,821.80 mi (7,759.93 km) |
| Boulder to Cabanillas del Campo | 5,021.04 mi (8,080.59 km) |
| Boulder to Cabra | 5,106.79 mi (8,218.59 km) |
| Boulder to Caceres | 4,938.78 mi (7,948.20 km) |
