| Llantrisant to Odessa (Texas) | 4,881.90 mi (7,856.66 km) |
| Llantrisant to Ogden (Utah) | 4,731.02 mi (7,613.85 km) |
| Llantrisant to Oildale (California) | 5,281.24 mi (8,499.33 km) |
| Llantrisant to Ojus (Florida) | 4,278.87 mi (6,886.17 km) |
| Llantrisant to Okemos (Michigan) | 3,659.58 mi (5,889.53 km) |
| Llantrisant to Oklahoma City (Oklahoma) | 4,512.04 mi (7,261.42 km) |
| Llantrisant to Okmulgee (Oklahoma) | 4,446.60 mi (7,156.10 km) |
| Llantrisant to Olathe (Kansas) | 4,239.36 mi (6,822.60 km) |
| Llantrisant to Old Jamestown (Missouri) | 4,066.48 mi (6,544.37 km) |
| Llantrisant to Oldsmar (Florida) | 4,280.54 mi (6,888.86 km) |
| Llantrisant to Olean (New York) | 3,449.28 mi (5,551.08 km) |
| Llantrisant to Olive Branch (Mississippi) | 4,236.08 mi (6,817.31 km) |
| Llantrisant to Olivehurst (California) | 5,154.04 mi (8,294.63 km) |
| Llantrisant to Olney (Maryland) | 3,521.54 mi (5,667.36 km) |
| Llantrisant to Olympia (Washington) | 4,742.48 mi (7,632.29 km) |
