| The Mumbles to Olympia Heights (Florida) | 4,271.28 mi (6,873.95 km) |
| The Mumbles to Omaha (Nebraska) | 4,145.96 mi (6,672.28 km) |
| The Mumbles to On Top of the World Designated Place (Florida) | 4,185.24 mi (6,735.50 km) |
| The Mumbles to Onalaska (Wisconsin) | 3,841.85 mi (6,182.86 km) |
| The Mumbles to Oneida (New York) | 3,269.67 mi (5,262.02 km) |
| The Mumbles to Oneonta (New York) | 3,271.20 mi (5,264.48 km) |
| The Mumbles to Ontario (California) | 5,290.42 mi (8,514.12 km) |
| The Mumbles to Ontario (Oregon) | 4,717.97 mi (7,592.85 km) |
| The Mumbles to Opa-locka (Florida) | 4,258.87 mi (6,853.99 km) |
| The Mumbles to Opelika (Alabama) | 4,140.01 mi (6,662.70 km) |
| The Mumbles to Opelousas (Louisiana) | 4,520.72 mi (7,275.39 km) |
| The Mumbles to Orange (California) | 5,310.85 mi (8,546.98 km) |
| The Mumbles to Orange (Texas) | 4,609.20 mi (7,417.79 km) |
| The Mumbles to Orange City (Florida) | 4,151.52 mi (6,681.22 km) |
| The Mumbles to Orangeburg (South Carolina) | 3,912.65 mi (6,296.80 km) |
