| Riihimaki to Olympia Heights (Florida) | 5,161.32 mi (8,306.35 km) |
| Riihimaki to Omaha (Nebraska) | 4,645.06 mi (7,475.50 km) |
| Riihimaki to On Top of the World Designated Place (Florida) | 5,016.05 mi (8,072.56 km) |
| Riihimaki to Onalaska (Wisconsin) | 4,368.57 mi (7,030.54 km) |
| Riihimaki to Oneida (New York) | 4,001.62 mi (6,439.98 km) |
| Riihimaki to Oneonta (New York) | 4,019.86 mi (6,469.35 km) |
| Riihimaki to Ontario (California) | 5,552.32 mi (8,935.59 km) |
| Riihimaki to Ontario (Oregon) | 4,886.01 mi (7,863.27 km) |
| Riihimaki to Opa-locka (Florida) | 5,148.19 mi (8,285.21 km) |
| Riihimaki to Opelika (Alabama) | 4,891.04 mi (7,871.38 km) |
| Riihimaki to Opelousas (Louisiana) | 5,206.27 mi (8,378.67 km) |
| Riihimaki to Orange (California) | 5,571.56 mi (8,966.55 km) |
| Riihimaki to Orange (Texas) | 5,275.86 mi (8,490.68 km) |
| Riihimaki to Orange City (Florida) | 4,996.70 mi (8,041.40 km) |
| Riihimaki to Orangeburg (South Carolina) | 4,711.50 mi (7,582.43 km) |
