Built of river stone at the end of the 13th century, for military purposes as a barbican in front of St. George's Gate, the former Praetoria of the Roman Castrum (entrance reserved for the governor, commander of LEG.XIII GEMINA, and Rome's officials), on the site where the medieval fortress of Bălgrad began to rise. The Habsburg army's plan from 1711 shows that the main access to the Bălgrad fortress was through St. George's Gate, which was protected by a circular barbican served by a drawbridge and a courtyard. This was used until the early 18th century.

The fog of 1442 brings the entrance of Iancu of Hunedoara into Alba Iulia Citadel, with the purpose of preparing the military campaign against the Ottomans who had invaded Transylvania. The battle took place in Sântimbru. After his death from plague in 1456, Iancu of Hunedoara is buried in Alba Iulia, in the Roman Catholic Cathedral of the city.

Through the Gate Tower enters the one whom history calls Vlad the Impaler as a result of being captured by Matthias Corvinus at Piatra Craiului Citadel. Here, an investigation takes place, which ends with his transfer to Buda and ultimately to Visegrád, where he remains in the former royal residence for 12 years.

During the construction of the new citadel, at the level of the substructures, the barbican was cleaned of ruins and preserved inside the new bastion of the Carolina Citadel, additionally adding to it; a pillar with a base formed of limestone blocks from the former Roman camp, vaults with vents, as well as a wooden bridge over the defense ditch (which would ignite in case of siege). The medieval tower of St. George's Gate is still visible today through the river stone at the base of this room. The iron doors at the entrance are original from the same period.

Built during the reign of Charles VI, in the seventh bastion, named St. John of Capistrano or of Transylvania, during the years 1715-1738, the space is part of the works hidden by a special importance, destined for the preservation and storage of weapons, gunpowder, and bullets. All of this happens in the context where the Citadel was the military center of Transylvania.

It was arranged in the round powder magazine during the siege of the Citadel in the spring of 1849 by Hungarian troops; it was operated by four horses (*3). The locations of the mill beams in the walls can still be observed today.

The space transforms into a wine cellar, an narrow iron walkway being placed over the defense ditch, the walls are plastered to conceal the brick, massive furniture made from tree trunks halves is brought in, as well as a cart full of barrels, from which wine is served. Dishes were cooked in the hall, where a huge grill was placed. The wine cellar was inaugurated in November 1968 by Nicolae Ceaușescu on the occasion of the celebration of the semi-centenary of the Union of Transylvania with Romania. At that time, it was the most well-known venue in the area, standing out for its parties with musicians. It operated until 1976.

The space comes under the administration of the Romanian Army, being used as a space for entertainment.

The Romanian Army uses the space as a "hideout" to protect members of the Securitate from the fury of the population.

We took over the abandoned space, lost in the mists of time, unable to keep pace with how sometimes we forget what brings value to a space. "PUB 13" was the first private investment in the Citadel, opening its doors in November 2003, after seven months of cleaning, sanitizing, restoring, and enhancing the space, becoming the first venue with events in the city.