| Hemel Hempstead to Nasaud | 1,151.46 mi (1,853.10 km) |
| Hemel Hempstead to Navodari | 1,426.69 mi (2,296.03 km) |
| Hemel Hempstead to Negresti-Oas | 1,093.17 mi (1,759.29 km) |
| Hemel Hempstead to Nehoiu | 1,293.06 mi (2,080.97 km) |
| Hemel Hempstead to Ocna Mures | 1,155.50 mi (1,859.59 km) |
| Hemel Hempstead to Odobesti | 1,311.43 mi (2,110.54 km) |
| Hemel Hempstead to Odorheiu Secuiesc | 1,218.93 mi (1,961.67 km) |
| Hemel Hempstead to Oltenita | 1,352.27 mi (2,176.26 km) |
| Hemel Hempstead to Onesti | 1,282.97 mi (2,064.73 km) |
| Hemel Hempstead to Oradea | 1,052.29 mi (1,693.50 km) |
| Hemel Hempstead to Orastie | 1,145.53 mi (1,843.55 km) |
| Hemel Hempstead to Oravita | 1,111.39 mi (1,788.61 km) |
| Hemel Hempstead to Orsova | 1,152.43 mi (1,854.65 km) |
| Hemel Hempstead to Otelu Rosu | 1,121.64 mi (1,805.10 km) |
| Hemel Hempstead to Otopeni | 1,311.50 mi (2,110.66 km) |
