We took an excursion to the tower - 200 dinars and to the town hall itself - 200 dinars (children are free). I liked both of them. Very beautiful mosaics, paintings in Hungarian motifs. The tours are either in English or Serbian.
It's very beautiful inside. A must-visit. Every day at 12 o'clock (except Sun and Mon) at the main entrance, a group is gathered and launched with an excursion.