| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| O Cach | city | Thanh Hoa | Vietnam | 19.55 | 105.78 | 36 | 64020 |
| Ong Do | city | Thanh Hoa | Vietnam | 19.95 | 105.92 | 32 | 48847 |
| Ong Doi | city | Thanh Hoa | Vietnam | 19.95 | 105.92 | 32 | 48847 |
| Ouang Duc | city | Thanh Hoa | Vietnam | 19.98 | 105.97 | 39 | 34753 |
| Oui Chu | city | Thanh Hoa | Vietnam | 19.88 | 105.78 | 45 | 141055 |
| Oui Mỹ | city | Thanh Hoa | Vietnam | 19.42 | 105.75 | 59 | 51813 |