| Round Rock to Nasaud | 5,969.12 mi (9,606.37 km) |
| Round Rock to Navodari | 6,257.01 mi (10,069.69 km) |
| Round Rock to Negresti-Oas | 5,908.00 mi (9,508.01 km) |
| Round Rock to Nehoiu | 6,126.74 mi (9,860.03 km) |
| Round Rock to Ocna Mures | 5,992.12 mi (9,643.39 km) |
| Round Rock to Odobesti | 6,132.86 mi (9,869.89 km) |
| Round Rock to Odorheiu Secuiesc | 6,045.87 mi (9,729.89 km) |
| Round Rock to Oltenita | 6,199.70 mi (9,977.45 km) |
| Round Rock to Onesti | 6,098.78 mi (9,815.04 km) |
| Round Rock to Oradea | 5,892.33 mi (9,482.79 km) |
| Round Rock to Orastie | 5,993.97 mi (9,646.36 km) |
| Round Rock to Oravita | 5,976.39 mi (9,618.07 km) |
| Round Rock to Orsova | 6,016.88 mi (9,683.23 km) |
| Round Rock to Otelu Rosu | 5,978.85 mi (9,622.03 km) |
| Round Rock to Otopeni | 6,157.28 mi (9,909.19 km) |
