The Gvozdansko Castle was probably built in the second half of the 15th century, due to mining rights of Croatian Zrinski noble family. The castle was first mentioned in 1488. Nikola III Zrinski and his son Nikola Šubić Zrinski frequently came to Gvozdansko in order to inspect the mines and the mint.
The Turks attempted to conquer the Gvozdansko Castle on several occasions. Three major attempts were made in 1561 by Malkoč-beg, in 1574 by Ferhad-beg, and in 1576 by Kapidži-pasha. The final siege by Ferhat-paša Sokolović with 10,000 soldiers, which was fought from 3 October 1577 to 13 January 1578, was much better prepared. That Siege of Gvozdansko ended with an Ottoman victory, after long and bloody siege. Ottomans managed to break into castle only after last defenders froze to death in harsh winter, having no wood or anything else to light the fire, on 13 January 1578.
Ottoman rule in Gvozansko lasted until 1718. Ottoman commander was stunned by the brave Croatian defenders, after witnessing frozen bodies of defenders still holding their muskets on combat positions in the ruined castle.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.