| Duchcov to Olympia Heights (Florida) | 5,034.25 mi (8,101.85 km) |
| Duchcov to Omaha (Nebraska) | 4,811.08 mi (7,742.68 km) |
| Duchcov to On Top of the World Designated Place (Florida) | 4,938.88 mi (7,948.35 km) |
| Duchcov to Onalaska (Wisconsin) | 4,512.52 mi (7,262.19 km) |
| Duchcov to Oneida (New York) | 3,995.00 mi (6,429.33 km) |
| Duchcov to Oneonta (New York) | 4,000.80 mi (6,438.67 km) |
| Duchcov to Ontario (California) | 5,881.13 mi (9,464.76 km) |
| Duchcov to Ontario (Oregon) | 5,261.59 mi (8,467.72 km) |
| Duchcov to Opa-locka (Florida) | 5,021.71 mi (8,081.66 km) |
| Duchcov to Opelika (Alabama) | 4,877.31 mi (7,849.27 km) |
| Duchcov to Opelousas (Louisiana) | 5,245.10 mi (8,441.17 km) |
| Duchcov to Orange (California) | 5,901.32 mi (9,497.26 km) |
| Duchcov to Orange (Texas) | 5,329.42 mi (8,576.87 km) |
| Duchcov to Orange City (Florida) | 4,907.43 mi (7,897.75 km) |
| Duchcov to Orangeburg (South Carolina) | 4,658.71 mi (7,497.47 km) |
