| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Oncieu | city | Rhone-Alpes | France | 45.96 | 5.47 | 2559 | 3318 |
| Oncina de la Valdoncina | city | Castilla y Leon | Spain | 42.55 | -5.66 | 2837 | 21413 |
| Oncins | city | Aragon | Spain | 42.46 | 0.21 | 3687 | 339 |
| Onciu | city | Galati | Romania | 46.05 | 27.93 | 830 | 4999 |
| Onciul | city | Galati | Romania | 46.05 | 27.93 | 830 | 4999 |
| Onciškiai | city | Lazdijai | Lithuania | 54.24 | 23.91 | 830 | 1066 |