| Clemmons to Olympia Heights (Florida) | 712.21 mi (1,146.20 km) |
| Clemmons to Omaha (Nebraska) | 917.69 mi (1,476.88 km) |
| Clemmons to On Top of the World Designated Place (Florida) | 491.14 mi (790.42 km) |
| Clemmons to Onalaska (Wisconsin) | 788.09 mi (1,268.32 km) |
| Clemmons to Oneida (New York) | 547.73 mi (881.49 km) |
| Clemmons to Oneonta (New York) | 526.98 mi (848.09 km) |
| Clemmons to Ontario (California) | 2,097.40 mi (3,375.44 km) |
| Clemmons to Ontario (Oregon) | 1,994.96 mi (3,210.58 km) |
| Clemmons to Opa-locka (Florida) | 700.11 mi (1,126.72 km) |
| Clemmons to Opelika (Alabama) | 367.73 mi (591.80 km) |
| Clemmons to Opelousas (Louisiana) | 774.51 mi (1,246.45 km) |
| Clemmons to Orange (California) | 2,113.49 mi (3,401.33 km) |
| Clemmons to Orange (Texas) | 874.23 mi (1,406.93 km) |
| Clemmons to Orange City (Florida) | 493.16 mi (793.67 km) |
| Clemmons to Orangeburg (South Carolina) | 177.55 mi (285.73 km) |
