| Catonsville to Noventa Vicentina | 4,298.76 mi (6,918.18 km) |
| Catonsville to Novi di Modena | 4,284.78 mi (6,895.69 km) |
| Catonsville to Novi Ligure | 4,197.92 mi (6,755.90 km) |
| Catonsville to Nuoro | 4,371.04 mi (7,034.51 km) |
| Catonsville to Occhiobello | 4,312.95 mi (6,941.02 km) |
| Catonsville to Oderzo | 4,322.59 mi (6,956.54 km) |
| Catonsville to Oggiono | 4,189.34 mi (6,742.09 km) |
| Catonsville to Olbia | 4,357.86 mi (7,013.30 km) |
| Catonsville to Oleggio | 4,164.48 mi (6,702.08 km) |
| Catonsville to Olgiate Comasco | 4,172.95 mi (6,715.72 km) |
| Catonsville to Olgiate Olona | 4,174.15 mi (6,717.65 km) |
| Catonsville to Omegna | 4,145.99 mi (6,672.33 km) |
| Catonsville to Opera | 4,196.45 mi (6,753.54 km) |
| Catonsville to Oppeano | 4,283.31 mi (6,893.31 km) |
| Catonsville to Orbassano | 4,135.76 mi (6,655.86 km) |
