| Pittsburgh to Olympia (Washington) | 2,162.08 mi (3,479.53 km) |
| Pittsburgh to Olympia Heights (Florida) | 1,016.97 mi (1,636.66 km) |
| Pittsburgh to Omaha (Nebraska) | 840.93 mi (1,353.34 km) |
| Pittsburgh to On Top of the World Designated Place (Florida) | 793.91 mi (1,277.68 km) |
| Pittsburgh to Onalaska (Wisconsin) | 621.93 mi (1,000.90 km) |
| Pittsburgh to Oneida (New York) | 287.41 mi (462.54 km) |
| Pittsburgh to Oneonta (New York) | 289.84 mi (466.45 km) |
| Pittsburgh to Ontario (California) | 2,100.02 mi (3,379.66 km) |
| Pittsburgh to Ontario (Oregon) | 1,892.87 mi (3,046.28 km) |
| Pittsburgh to Opa-locka (Florida) | 1,004.74 mi (1,616.98 km) |
| Pittsburgh to Opelika (Alabama) | 615.07 mi (989.86 km) |
| Pittsburgh to Opelousas (Louisiana) | 964.16 mi (1,551.67 km) |
| Pittsburgh to Orange (California) | 2,117.84 mi (3,408.33 km) |
| Pittsburgh to Orange (Texas) | 1,052.40 mi (1,693.67 km) |
| Pittsburgh to Orange City (Florida) | 798.37 mi (1,284.85 km) |
