| Kazanlak to Olympia Heights (Florida) | 5,765.92 mi (9,279.35 km) |
| Kazanlak to Omaha (Nebraska) | 5,590.66 mi (8,997.29 km) |
| Kazanlak to On Top of the World Designated Place (Florida) | 5,686.28 mi (9,151.18 km) |
| Kazanlak to Onalaska (Wisconsin) | 5,292.08 mi (8,516.79 km) |
| Kazanlak to Oneida (New York) | 4,763.48 mi (7,666.08 km) |
| Kazanlak to Oneonta (New York) | 4,767.26 mi (7,672.16 km) |
| Kazanlak to Ontario (California) | 6,646.96 mi (10,697.24 km) |
| Kazanlak to Ontario (Oregon) | 6,014.52 mi (9,679.44 km) |
| Kazanlak to Opa-locka (Florida) | 5,753.69 mi (9,259.68 km) |
| Kazanlak to Opelika (Alabama) | 5,639.80 mi (9,076.38 km) |
| Kazanlak to Opelousas (Louisiana) | 6,014.91 mi (9,680.06 km) |
| Kazanlak to Orange (California) | 6,667.02 mi (10,729.53 km) |
| Kazanlak to Orange (Texas) | 6,101.01 mi (9,818.63 km) |
| Kazanlak to Orange City (Florida) | 5,651.78 mi (9,095.66 km) |
| Kazanlak to Orangeburg (South Carolina) | 5,414.27 mi (8,713.43 km) |
