| Euclid to Orbetello | 4,495.35 mi (7,234.57 km) |
| Euclid to Oria | 4,842.32 mi (7,792.96 km) |
| Euclid to Oristano | 4,481.79 mi (7,212.75 km) |
| Euclid to Orta Nova | 4,727.81 mi (7,608.68 km) |
| Euclid to Orte | 4,543.65 mi (7,312.30 km) |
| Euclid to Ortona | 4,631.64 mi (7,453.90 km) |
| Euclid to Orvieto | 4,521.94 mi (7,277.36 km) |
| Euclid to Orzinuovi | 4,329.10 mi (6,967.01 km) |
| Euclid to Osimo | 4,548.29 mi (7,319.77 km) |
| Euclid to Ospitaletto | 4,329.01 mi (6,966.87 km) |
| Euclid to Ostuni | 4,830.29 mi (7,773.60 km) |
| Euclid to Ottaviano | 4,696.33 mi (7,558.01 km) |
| Euclid to Ovada | 4,304.35 mi (6,927.19 km) |
| Euclid to Ozieri | 4,473.33 mi (7,199.12 km) |
| Euclid to Paceco | 4,732.06 mi (7,615.52 km) |
