Šabac Fortress

Šabac fortress (Serbian: Шабачка тврђава), also known as Bigir Delen in Turkish, is a fortress next to modern day Šabac, on the right riverbank of Sava.

History
Originally the location where the fortress was built was a trading square of the settlement known as Zaslon, where the merchants from Ragusa would trade their goods.

The fortress was built in 1471 by Isa-Beg Ishaković, but soon afterwards, in 1476, it was conquered by the Hungarian army helped by Serbian despot Vuk Grgurević, who kept the Šabac fortress under his control for more than four decades. In 1521, on his campaign on the way to Belgrade, Suleiman the Magnificent conquered Šabac. As soon as he got hold of it, he had the earth palisade fortifications replaced with bulwark constructions with towers. In the period from 1717 until 1739, during temporary Austrian occupation, the fortress underwent significant adaptations and its surface was extended with additional construction of outer fortifications.

Characteristics
Originally, the fortress was made of wood with earth ramparts and trenches, on an artificial island. Subsequently, the fortress was mostly constructed in brick. It has symmetrical rectangular foundation, with one circular tower in each corner. Its construction is similar to the fortress in Kladovo, which indicates that both fortresses were built around the same time.