| Shannon to Olympia Heights (Florida) | 4,059.25 mi (6,532.73 km) |
| Shannon to Omaha (Nebraska) | 3,926.74 mi (6,319.48 km) |
| Shannon to On Top of the World Designated Place (Florida) | 3,969.28 mi (6,387.94 km) |
| Shannon to Onalaska (Wisconsin) | 3,622.36 mi (5,829.63 km) |
| Shannon to Oneida (New York) | 3,049.13 mi (4,907.10 km) |
| Shannon to Oneonta (New York) | 3,050.94 mi (4,910.01 km) |
| Shannon to Ontario (California) | 5,078.02 mi (8,172.29 km) |
| Shannon to Ontario (Oregon) | 4,513.12 mi (7,263.17 km) |
| Shannon to Opa-locka (Florida) | 4,046.76 mi (6,512.64 km) |
| Shannon to Opelika (Alabama) | 3,920.74 mi (6,309.81 km) |
| Shannon to Opelousas (Louisiana) | 4,300.32 mi (6,920.70 km) |
| Shannon to Orange (California) | 5,098.45 mi (8,205.16 km) |
| Shannon to Orange (Texas) | 4,388.59 mi (7,062.76 km) |
| Shannon to Orange City (Florida) | 3,936.29 mi (6,334.85 km) |
| Shannon to Orangeburg (South Carolina) | 3,694.74 mi (5,946.11 km) |
