Sahat kula – Tora, i.e. the Clock Tower ) was built in 1667 at the orders of Sultan Mahmud. During the Turkish rule, these were the main city gates. There is a sculpture of Madonna in its arcade (called the “Black Madonna” since it was built from the burnt wood in remembrance of the founder of the city, Tvrtko I Kotromanić, and was done in the form of bas-relief by Afran Hozić from Sarajevo).
The clock on the tower was replaced by an electric one only in 1995 and it was a gift from the city of Zemun.
text: http://hercegnovi.travel