| Ostrow Mazowiecka to Karlovo | 714.47 mi (1,149.84 km) |
| Ostrow Mazowiecka to Karnobat | 740.66 mi (1,191.98 km) |
| Ostrow Mazowiecka to Kavarna | 711.28 mi (1,144.69 km) |
| Ostrow Mazowiecka to Kazanlak | 721.94 mi (1,161.86 km) |
| Ostrow Mazowiecka to Knezha | 650.32 mi (1,046.59 km) |
| Ostrow Mazowiecka to Kostinbrod | 692.45 mi (1,114.39 km) |
| Ostrow Mazowiecka to Kozloduy | 628.61 mi (1,011.65 km) |
| Ostrow Mazowiecka to Kyustendil | 727.54 mi (1,170.86 km) |
| Ostrow Mazowiecka to Levski | 668.47 mi (1,075.79 km) |
| Ostrow Mazowiecka to Lom | 623.08 mi (1,002.75 km) |
| Ostrow Mazowiecka to Lovech | 680.27 mi (1,094.78 km) |
| Ostrow Mazowiecka to Lukovit | 671.43 mi (1,080.57 km) |
| Ostrow Mazowiecka to Lyaskovets | 692.83 mi (1,115.00 km) |
| Ostrow Mazowiecka to Mezdra | 671.87 mi (1,081.27 km) |
| Ostrow Mazowiecka to Momchilgrad | 795.54 mi (1,280.29 km) |
