| Santarem to Orbetello | 1,060.87 mi (1,707.31 km) |
| Santarem to Oria | 1,393.32 mi (2,242.33 km) |
| Santarem to Oristano | 919.95 mi (1,480.52 km) |
| Santarem to Orta Nova | 1,289.80 mi (2,075.74 km) |
| Santarem to Orte | 1,120.61 mi (1,803.45 km) |
| Santarem to Ortona | 1,222.73 mi (1,967.80 km) |
| Santarem to Orvieto | 1,108.17 mi (1,783.43 km) |
| Santarem to Orzinuovi | 1,039.10 mi (1,672.27 km) |
| Santarem to Osimo | 1,182.71 mi (1,903.38 km) |
| Santarem to Ospitaletto | 1,048.84 mi (1,687.94 km) |
| Santarem to Ostuni | 1,389.39 mi (2,236.01 km) |
| Santarem to Ottaviano | 1,226.74 mi (1,974.25 km) |
| Santarem to Ovada | 963.51 mi (1,550.63 km) |
| Santarem to Ozieri | 940.55 mi (1,513.67 km) |
| Santarem to Paceco | 1,147.18 mi (1,846.21 km) |
