| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Rio Olote | city | Oaxaca | Mexico | 16.31 | -97.34 | 5318 | 3936 |
| Rio Oro | city | Oaxaca | Mexico | 17.70 | -97.61 | 6709 | 3720 |
| Rio Ostuta | city | Oaxaca | Mexico | 16.50 | -94.43 | 223 | 1123 |
| Rio Oteros | city | Chihuahua | Mexico | 27.75 | -107.70 | 7549 | 1315 |