Sisak Fortress

Sisak Fortress, also known as Stari grad, was built at the confluence of the Kupa and Sava rivers to resist Ottoman advances. Zagreb Cathedral Chapter began construction in 1544, and the fort was serving its core defensive purpose by 1550. Its triangular plan is defined by three powerful cylindrical corner towers, and some of its fabric reused material from Roman Siscia. The Battle of Sisak, a major Christian victory over the Ottoman army, took place beside it on 22 June 1593. The fortress is a significant example of military architecture, with museum interpretation focused on Sisak’s past.