| Merrick to Olympia Heights (Florida) | 1,102.57 mi (1,774.41 km) |
| Merrick to Omaha (Nebraska) | 1,171.48 mi (1,885.31 km) |
| Merrick to On Top of the World Designated Place (Florida) | 937.66 mi (1,509.02 km) |
| Merrick to Onalaska (Wisconsin) | 927.93 mi (1,493.35 km) |
| Merrick to Oneida (New York) | 199.62 mi (321.26 km) |
| Merrick to Oneonta (New York) | 147.13 mi (236.79 km) |
| Merrick to Ontario (California) | 2,436.53 mi (3,921.22 km) |
| Merrick to Ontario (Oregon) | 2,204.15 mi (3,547.24 km) |
| Merrick to Opa-locka (Florida) | 1,089.39 mi (1,753.21 km) |
| Merrick to Opelika (Alabama) | 855.50 mi (1,376.79 km) |
| Merrick to Opelousas (Louisiana) | 1,250.17 mi (2,011.96 km) |
| Merrick to Orange (California) | 2,454.45 mi (3,950.06 km) |
| Merrick to Orange (Texas) | 1,345.77 mi (2,165.81 km) |
| Merrick to Orange City (Florida) | 919.90 mi (1,480.44 km) |
| Merrick to Orangeburg (South Carolina) | 637.61 mi (1,026.14 km) |
