Today, the colloquial name Eastern Suburbs is borne by a small fortification on the most protruding part of the Danube slope. It was built in the last stage of the development of medieval fortifications, in the first years of the reign of King Matthias Corvinus (1458–1490), at the same time as the cannon tower at the entrance to the Danube port, today’s Nebojsa Tower. In order to defend the northeastern part of the city in the conditions of war with artillery weapons, this fortification connected the two most important entrances to the fortress with ramparts — the Zindan Gate of the Upper Town and the Eastern Gate of the Lower Town. At the junction of the two ramparts, a cannon tower was erected, today known as Jaksic Tower.

The interior of the fortification was not suitable for erecting facilities since it was mostly located on a slope. However, already during the second half of the 15th century, there was a spacious building at its foot, partially cut into the slope. This building, the remains of which can be seen along the path that descends from the St. Petka Chapel to the East Gate and the Lower Town, was erected at the same time as the walls of the suburbs. Its original purpose is not known, but according to some plans of Belgrade from the end of the 17th century, the building served as a warehouse for military equipment and gunpowder.

On the slope, in the immediate vicinity of this building, there are two revered sanctuaries, the Ruzica Church and the St. Petka Chapel.