| Potomac to Hoyo de Manzanares | 3,772.49 mi (6,071.23 km) |
| Potomac to Huelva | 3,719.73 mi (5,986.32 km) |
| Potomac to Huercal de Almeria | 3,954.63 mi (6,364.36 km) |
| Potomac to Huercal-Overa | 3,963.57 mi (6,378.75 km) |
| Potomac to Huesca | 3,893.45 mi (6,265.90 km) |
| Potomac to Huetor Vega | 3,890.48 mi (6,261.12 km) |
| Potomac to Huetor-Tajar | 3,865.43 mi (6,220.80 km) |
| Potomac to Humanes de Madrid | 3,785.90 mi (6,092.81 km) |
| Potomac to Ibi | 3,990.91 mi (6,422.75 km) |
| Potomac to Ibiza | 4,078.47 mi (6,563.67 km) |
| Potomac to Icod de los Vinos | 3,491.12 mi (5,618.41 km) |
| Potomac to Igualada | 4,004.54 mi (6,444.68 km) |
| Potomac to Illescas | 3,789.55 mi (6,098.69 km) |
| Potomac to Inca | 4,123.18 mi (6,635.61 km) |
| Potomac to Ingenio | 3,573.01 mi (5,750.20 km) |
