| Answer | Crossword Clue |
|---|---|
| ELBA | Portoferraio is its principal port |
| ELBA | Portoferraio is its chief port. |
| ELBA | Its main town is Portoferraio |
| ELBA | Its chief town is Portoferraio |
| ELBA | Portoferraio is its chief town |
| MORAVIA | Brno is its principal city |
| RUHR | Its principal city is Essen |
| NIOBIUM | Its principal ore is columbite |
