| Highlands Ranch to Oberkirch | 5,106.91 mi (8,218.78 km) |
| Highlands Ranch to Obernburg am Main | 5,081.00 mi (8,177.07 km) |
| Highlands Ranch to Obernkirchen | 4,966.98 mi (7,993.58 km) |
| Highlands Ranch to Oberschleissheim | 5,236.29 mi (8,426.99 km) |
| Highlands Ranch to Oberstdorf | 5,234.10 mi (8,423.47 km) |
| Highlands Ranch to Obertraubling | 5,220.94 mi (8,402.30 km) |
| Highlands Ranch to Obertshausen | 5,060.31 mi (8,143.78 km) |
| Highlands Ranch to Oberursel | 5,045.56 mi (8,120.05 km) |
| Highlands Ranch to Ochsenfurt | 5,120.13 mi (8,240.06 km) |
| Highlands Ranch to Ochsenhausen | 5,191.31 mi (8,354.60 km) |
| Highlands Ranch to Ochtrup | 4,908.77 mi (7,899.89 km) |
| Highlands Ranch to Odenthal | 4,959.62 mi (7,981.74 km) |
| Highlands Ranch to Oelde | 4,956.40 mi (7,976.55 km) |
| Highlands Ranch to Oelsnitz | 5,150.37 mi (8,288.73 km) |
| Highlands Ranch to Oer-Erkenschwick | 4,936.28 mi (7,944.17 km) |
