| Barbastro to Olympia Heights (Florida) | 4,582.96 mi (7,375.57 km) |
| Barbastro to Omaha (Nebraska) | 4,668.81 mi (7,513.73 km) |
| Barbastro to On Top of the World Designated Place (Florida) | 4,539.98 mi (7,306.39 km) |
| Barbastro to Onalaska (Wisconsin) | 4,362.86 mi (7,021.35 km) |
| Barbastro to Oneida (New York) | 3,717.69 mi (5,983.05 km) |
| Barbastro to Oneonta (New York) | 3,710.21 mi (5,971.01 km) |
| Barbastro to Ontario (California) | 5,867.94 mi (9,443.54 km) |
| Barbastro to Ontario (Oregon) | 5,331.92 mi (8,580.89 km) |
| Barbastro to Opa-locka (Florida) | 4,571.52 mi (7,357.15 km) |
| Barbastro to Opelika (Alabama) | 4,544.33 mi (7,313.39 km) |
| Barbastro to Opelousas (Louisiana) | 4,947.90 mi (7,962.88 km) |
| Barbastro to Orange (California) | 5,888.32 mi (9,476.33 km) |
| Barbastro to Orange (Texas) | 5,043.32 mi (8,116.45 km) |
| Barbastro to Orange City (Florida) | 4,498.14 mi (7,239.06 km) |
| Barbastro to Orangeburg (South Carolina) | 4,297.23 mi (6,915.72 km) |
