| Cincinnati to Olivares | 4,109.52 mi (6,613.64 km) |
| Cincinnati to Olivenza | 4,023.04 mi (6,474.46 km) |
| Cincinnati to Olot | 4,352.85 mi (7,005.23 km) |
| Cincinnati to Onate | 4,105.28 mi (6,606.80 km) |
| Cincinnati to Onda | 4,303.48 mi (6,925.78 km) |
| Cincinnati to Onteniente | 4,326.36 mi (6,962.61 km) |
| Cincinnati to Orihuela | 4,335.71 mi (6,977.65 km) |
| Cincinnati to Osuna | 4,166.30 mi (6,705.01 km) |
| Cincinnati to Ourense | 3,876.94 mi (6,239.34 km) |
| Cincinnati to Oviedo | 3,940.09 mi (6,340.97 km) |
| Cincinnati to Paiporta | 4,314.48 mi (6,943.49 km) |
| Cincinnati to Pajara | 4,013.34 mi (6,458.85 km) |
| Cincinnati to Palafolls | 4,382.13 mi (7,052.36 km) |
| Cincinnati to Palafrugell | 4,391.95 mi (7,068.16 km) |
| Cincinnati to Palamos | 4,392.91 mi (7,069.70 km) |
