| Gladbeck to Oestrich-Winkel | 117.28 mi (188.74 km) |
| Gladbeck to Offenburg | 218.44 mi (351.55 km) |
| Gladbeck to Oftersheim | 167.58 mi (269.70 km) |
| Gladbeck to Ohrdruf | 170.84 mi (274.93 km) |
| Gladbeck to Ohringen | 197.95 mi (318.58 km) |
| Gladbeck to Olbernhau | 282.95 mi (455.36 km) |
| Gladbeck to Olching | 302.57 mi (486.94 km) |
| Gladbeck to Oldenburg | 121.01 mi (194.75 km) |
| Gladbeck to Oldenburg in Holstein | 249.46 mi (401.47 km) |
| Gladbeck to Olfen | 20.65 mi (33.24 km) |
| Gladbeck to Olpe | 53.35 mi (85.86 km) |
| Gladbeck to Olsberg | 66.98 mi (107.80 km) |
| Gladbeck to Oranienburg | 278.04 mi (447.46 km) |
| Gladbeck to Ortenberg | 123.53 mi (198.80 km) |
| Gladbeck to Oschatz | 265.06 mi (426.57 km) |
