| Potomac to Barking | 3,673.95 mi (5,912.66 km) |
| Potomac to Barnet | 3,660.27 mi (5,890.64 km) |
| Potomac to Barnoldswick | 3,534.84 mi (5,688.77 km) |
| Potomac to Barnsley | 3,569.57 mi (5,744.67 km) |
| Potomac to Barnstaple | 3,513.17 mi (5,653.90 km) |
| Potomac to Barrhead | 3,418.46 mi (5,501.48 km) |
| Potomac to Barri | 3,539.49 mi (5,696.27 km) |
| Potomac to Barrow in Furness | 3,490.68 mi (5,617.70 km) |
| Potomac to Barton upon Humber | 3,607.46 mi (5,805.65 km) |
| Potomac to Barton upon Irwell | 3,536.28 mi (5,691.10 km) |
| Potomac to Barwell | 3,594.43 mi (5,784.68 km) |
| Potomac to Basford | 3,593.23 mi (5,782.75 km) |
| Potomac to Basildon | 3,689.72 mi (5,938.04 km) |
| Potomac to Basingstoke | 3,632.22 mi (5,845.49 km) |
| Potomac to Bath | 3,577.51 mi (5,757.45 km) |
