| Nieuwkoop to Oerlinghausen | 166.27 mi (267.59 km) |
| Nieuwkoop to Oestrich-Winkel | 205.98 mi (331.49 km) |
| Nieuwkoop to Offenburg | 292.26 mi (470.34 km) |
| Nieuwkoop to Oftersheim | 256.04 mi (412.06 km) |
| Nieuwkoop to Ohrdruf | 273.03 mi (439.40 km) |
| Nieuwkoop to Ohringen | 292.13 mi (470.15 km) |
| Nieuwkoop to Olbernhau | 383.40 mi (617.01 km) |
| Nieuwkoop to Olching | 399.33 mi (642.65 km) |
| Nieuwkoop to Oldenburg | 158.95 mi (255.80 km) |
| Nieuwkoop to Oldenburg in Holstein | 292.01 mi (469.94 km) |
| Nieuwkoop to Olfen | 115.99 mi (186.67 km) |
| Nieuwkoop to Olpe | 154.31 mi (248.34 km) |
| Nieuwkoop to Olsberg | 169.00 mi (271.99 km) |
| Nieuwkoop to Oranienburg | 358.49 mi (576.93 km) |
| Nieuwkoop to Ortenberg | 224.25 mi (360.89 km) |
