| Middle Island to Olympia Heights (Florida) | 1,130.11 mi (1,818.74 km) |
| Middle Island to Omaha (Nebraska) | 1,200.32 mi (1,931.72 km) |
| Middle Island to On Top of the World Designated Place (Florida) | 969.20 mi (1,559.78 km) |
| Middle Island to Onalaska (Wisconsin) | 952.66 mi (1,533.15 km) |
| Middle Island to Oneida (New York) | 205.87 mi (331.32 km) |
| Middle Island to Oneonta (New York) | 154.08 mi (247.97 km) |
| Middle Island to Ontario (California) | 2,467.25 mi (3,970.66 km) |
| Middle Island to Ontario (Oregon) | 2,228.23 mi (3,586.00 km) |
| Middle Island to Opa-locka (Florida) | 1,116.92 mi (1,797.51 km) |
| Middle Island to Opelika (Alabama) | 890.75 mi (1,433.52 km) |
| Middle Island to Opelousas (Louisiana) | 1,285.87 mi (2,069.40 km) |
| Middle Island to Orange (California) | 2,485.25 mi (3,999.63 km) |
| Middle Island to Orange (Texas) | 1,381.47 mi (2,223.26 km) |
| Middle Island to Orange City (Florida) | 950.34 mi (1,529.42 km) |
| Middle Island to Orangeburg (South Carolina) | 670.98 mi (1,079.83 km) |
