| Difficult Run to Barberino di Mugello | 4,370.34 mi (7,033.38 km) |
| Difficult Run to Barcellona-Pozzo di Gotto | 4,758.20 mi (7,657.59 km) |
| Difficult Run to Bareggio | 4,224.75 mi (6,799.07 km) |
| Difficult Run to Barga | 4,335.01 mi (6,976.52 km) |
| Difficult Run to Bari | 4,718.18 mi (7,593.18 km) |
| Difficult Run to Barletta | 4,685.57 mi (7,540.69 km) |
| Difficult Run to Baronissi | 4,640.53 mi (7,468.22 km) |
| Difficult Run to Barrafranca | 4,741.68 mi (7,631.00 km) |
| Difficult Run to Bassano del Grappa | 4,332.11 mi (6,971.86 km) |
| Difficult Run to Battipaglia | 4,654.75 mi (7,491.09 km) |
| Difficult Run to Beinasco | 4,178.46 mi (6,724.58 km) |
| Difficult Run to Bellinzago Novarese | 4,206.00 mi (6,768.90 km) |
| Difficult Run to Belluno | 4,339.91 mi (6,984.41 km) |
| Difficult Run to Belmonte Mezzagno | 4,678.52 mi (7,529.35 km) |
| Difficult Run to Belpasso | 4,769.25 mi (7,675.37 km) |
