| Difficult Run to Nasaud | 4,786.58 mi (7,703.26 km) |
| Difficult Run to Navodari | 5,071.55 mi (8,161.88 km) |
| Difficult Run to Negresti-Oas | 4,725.84 mi (7,605.50 km) |
| Difficult Run to Nehoiu | 4,938.52 mi (7,947.77 km) |
| Difficult Run to Ocna Mures | 4,801.31 mi (7,726.96 km) |
| Difficult Run to Odobesti | 4,950.54 mi (7,967.12 km) |
| Difficult Run to Odorheiu Secuiesc | 4,860.13 mi (7,821.62 km) |
| Difficult Run to Oltenita | 5,004.56 mi (8,054.06 km) |
| Difficult Run to Onesti | 4,918.59 mi (7,915.71 km) |
| Difficult Run to Oradea | 4,699.00 mi (7,562.31 km) |
| Difficult Run to Orastie | 4,797.07 mi (7,720.14 km) |
| Difficult Run to Oravita | 4,768.85 mi (7,674.73 km) |
| Difficult Run to Orsova | 4,809.85 mi (7,740.70 km) |
| Difficult Run to Otelu Rosu | 4,776.71 mi (7,687.38 km) |
| Difficult Run to Otopeni | 4,962.86 mi (7,986.95 km) |
