| Johnstown to Oakley (California) | 2,275.04 mi (3,661.32 km) |
| Johnstown to Oakton (Virginia) | 131.44 mi (211.54 km) |
| Johnstown to Oakville (Missouri) | 621.99 mi (1,001.00 km) |
| Johnstown to Oatfield (Oregon) | 2,211.63 mi (3,559.27 km) |
| Johnstown to Ocala (Florida) | 791.63 mi (1,274.01 km) |
| Johnstown to Ocean Acres (New Jersey) | 248.66 mi (400.18 km) |
| Johnstown to Ocean City (New Jersey) | 240.53 mi (387.10 km) |
| Johnstown to Ocean Pines (Maryland) | 241.97 mi (389.41 km) |
| Johnstown to Ocean Pointe (Hawaii) | 4,720.50 mi (7,596.92 km) |
| Johnstown to Ocean Springs (Mississippi) | 881.15 mi (1,418.07 km) |
| Johnstown to Oceanside (California) | 2,162.64 mi (3,480.43 km) |
| Johnstown to Oceanside (New York) | 278.41 mi (448.06 km) |
| Johnstown to Ocoee (Florida) | 825.03 mi (1,327.76 km) |
| Johnstown to Oconomowoc (Wisconsin) | 529.36 mi (851.93 km) |
| Johnstown to Odenton (Maryland) | 146.88 mi (236.39 km) |
