The city of Slavonski Brod, Croatia was an important strategic and traffic center controlling the border crossing towards Turkey and connecting main commercial trails at the time.
Along with the fortified baroque towns of Slavonia, Osijek and Stara Gradiška, it belongs to the great defense system on the border towards the Turkish Empire, designed by Prince Eugene of Savoy in the first half of the 18th century.
It was constructed by peasants of the Military Border under forced labor more specifically 634 a day, who also gave 53 horse-drawn carts daily for the transport of material.
In the curtain wall interior there are rooms for accommodation of men and ammunition, as well as the workshops required for the Fortress functioning, with passages across the middle.
In the Cavalier interior there were up to 108 large rooms of identical dimensions - casemates, used for the army logistic purposes, namely for the accommodation of the soldiers, artillery workshops, cart-wright's, locksmith's, armorer's shop, armory, bakery, storage, hospital, pharmacy.
Today, the renovated part of the southwestern tract of the Cavalier, on the gross area of 1,800 square metres (19,000 sq ft), houses the unique Ružić Gallery with the first permanent exhibition of the Croatian modern art of the second half of the 20th century.
The external defense zone consisted of ravelins - triangular bastions protecting the main walls and obstructing the enemy access to the Fortress.
Due to the rapid development of the siege techniques, the Brod Fortress lost its defensive task already by the mid 19th century.