| Boulder to Baraboo (Wisconsin) | 833.01 mi (1,340.61 km) |
| Boulder to Barberton (Ohio) | 1,240.22 mi (1,995.95 km) |
| Boulder to Bardstown (Kentucky) | 1,072.81 mi (1,726.53 km) |
| Boulder to Barrington (Illinois) | 902.20 mi (1,451.94 km) |
| Boulder to Barstow (California) | 737.79 mi (1,187.35 km) |
| Boulder to Bartlesville (Oklahoma) | 552.54 mi (889.22 km) |
| Boulder to Bartlett (Illinois) | 897.47 mi (1,444.34 km) |
| Boulder to Bartlett (Tennessee) | 905.53 mi (1,457.31 km) |
| Boulder to Bartow (Florida) | 1,575.65 mi (2,535.76 km) |
| Boulder to Batavia (Illinois) | 891.70 mi (1,435.06 km) |
| Boulder to Batavia (New York) | 1,409.41 mi (2,268.23 km) |
| Boulder to Batesville (Arkansas) | 798.13 mi (1,284.47 km) |
| Boulder to Baton Rouge (Louisiana) | 1,033.80 mi (1,663.74 km) |
| Boulder to Battle Creek (Michigan) | 1,050.81 mi (1,691.11 km) |
| Boulder to Battle Ground (Washington) | 958.45 mi (1,542.48 km) |
