| Barrow in Furness to Olympia Heights (Florida) | 4,283.99 mi (6,894.42 km) |
| Barrow in Furness to Omaha (Nebraska) | 4,087.88 mi (6,578.80 km) |
| Barrow in Furness to On Top of the World Designated Place (Florida) | 4,185.36 mi (6,735.68 km) |
| Barrow in Furness to Onalaska (Wisconsin) | 3,785.87 mi (6,092.77 km) |
| Barrow in Furness to Oneida (New York) | 3,244.49 mi (5,221.50 km) |
| Barrow in Furness to Oneonta (New York) | 3,249.20 mi (5,229.09 km) |
| Barrow in Furness to Ontario (California) | 5,205.95 mi (8,378.17 km) |
| Barrow in Furness to Ontario (Oregon) | 4,618.27 mi (7,432.39 km) |
| Barrow in Furness to Opa-locka (Florida) | 4,271.37 mi (6,874.11 km) |
| Barrow in Furness to Opelika (Alabama) | 4,124.47 mi (6,637.70 km) |
| Barrow in Furness to Opelousas (Louisiana) | 4,495.61 mi (7,234.99 km) |
| Barrow in Furness to Orange (California) | 5,226.34 mi (8,410.98 km) |
| Barrow in Furness to Orange (Texas) | 4,581.33 mi (7,372.94 km) |
| Barrow in Furness to Orange City (Florida) | 4,154.34 mi (6,685.76 km) |
| Barrow in Furness to Orangeburg (South Carolina) | 3,904.87 mi (6,284.28 km) |
