| Kelso to Olympia Heights (Florida) | 2,721.53 mi (4,379.88 km) |
| Kelso to Omaha (Nebraska) | 1,375.00 mi (2,212.85 km) |
| Kelso to On Top of the World Designated Place (Florida) | 2,478.01 mi (3,987.97 km) |
| Kelso to Onalaska (Wisconsin) | 1,545.12 mi (2,486.64 km) |
| Kelso to Oneida (New York) | 2,298.62 mi (3,699.26 km) |
| Kelso to Oneonta (New York) | 2,342.95 mi (3,770.61 km) |
| Kelso to Ontario (California) | 879.91 mi (1,416.08 km) |
| Kelso to Ontario (Oregon) | 322.84 mi (519.56 km) |
| Kelso to Opa-locka (Florida) | 2,717.22 mi (4,372.94 km) |
| Kelso to Opelika (Alabama) | 2,182.37 mi (3,512.19 km) |
| Kelso to Opelousas (Louisiana) | 1,968.36 mi (3,167.77 km) |
| Kelso to Orange (California) | 892.05 mi (1,435.61 km) |
| Kelso to Orange (Texas) | 1,913.58 mi (3,079.61 km) |
| Kelso to Orange City (Florida) | 2,532.02 mi (4,074.89 km) |
| Kelso to Orangeburg (South Carolina) | 2,362.35 mi (3,801.83 km) |
