A monument of architecture of national importance (security number 666 N).
The castle on mountain Bona in Kremenets is not only a picturesque architectural heritage, but also a witness of historical events and is one of the oldest fortifications in Ukraine. The first mention of the building in Polish sources dates back to the second half of the 11th century, while in Ukrainian chronicles the town is mentioned in 1227.
Due to its location (the height of the hill itself is 397 m above sea level), the castle survived the attack of Khan Batu’s horde in early 1241. In 1259, warriors of the Volynian prince Vasylko were forced to demolish the defensive structures at the demand of the Khan of Mongolia.
The construction of the new castle probably begun by the Polish king Casimir III in the XIV century, later this work was continued by the Lithuanian princes, since the town and fortress passed to their possession in 1382.
The stronghold acquired its final form in the middle of the XVI century. In the
1530s Vilnius Bishop Janush, by that time the headman of Kremenets, began the reconstruction of the castle. In 1536 the town, together with the fortress and adjacent territories, became the property of the wife of the Polish king Sigismund I the Old – Bona Sforza d’Argona.
After a six-week siege fall in 1648 the castle was taken by the seven thousand Cossack regiment of Maxim Kryvonis with the support of local rebels. The fortress lost its defensive significance and was never rebuilt again, even considering some attempts. Today it is an architectural monument of national importance.