The Alba Carolina - Citade Alba Iulia Fortress
History
During the Middle Ages it was rebuilt several times, but its greatest transformation is linked to Prince Gabriel Bethlen, who had two bastions constructed. However, the defensive system proved ineffective during the Tatar attacks of 1658 and 1661, after which Prince Michael Apafi deemed it safer to move his seat to Făgăraș. The fortress, left to decay, was only rebuilt by the Habsburgs, who renamed it Carlsburg (Károlyvár) in honor of the emperor. The foundation stone of the new fortress, designed by the Italian architect Giovanni Morando Visconti, was laid on November 4, 1715, and construction was completed in 1738.
This fortification, built to meet contemporary needs, was still strong enough during the Hungarian War of Independence of 1848–1849 that the Hungarian honvéd army, led by General Bem, was unable to capture it. At the turn of the 17th and 18th centuries, the fortress was rebuilt as a star-shaped stronghold with covered passageways and armories, while the inner fortress retained its square layout, surrounded by three rows of walls, seven bastions, and six ravelins.
Style
The bastion walls are 2.5 meters thick at the base and more than 10 meters high, built mainly of brick, with carved stones used only at the edges and for decoration. The walls, reinforced with buttresses, were built at a slight angle rather than vertically, to better withstand artillery fire, and the fortress had its own defensive structures extending to the walls and moats linked to the bastions.
The fortress had six gates, three on the eastern side and three on the western side. During the Rákóczi War of Independence, the last Transylvanian Diet to elect a prince was held here.Famous residents
The fortress had six gates, three on the eastern side and three on the western side. During the Rákóczi War of Independence, the last Transylvanian Diet to elect a prince was held here.Renovation
Fully restored and landscaped, the fortress presents itself as a heritage ensemble: a medieval structure built on the foundations of a Roman fort, strengthened in the 18th century with outer defensive works. A section of the Roman main road, the Via Principalis, is still visible today.
Present day
Today, the Gyulafehérvár fortress is a historic monument in Alba County, Romania, listed under the code AB-II-a-A-00088 in the Register of Historical Monuments. It has also been proposed as a UNESCO World Heritage Site as part of the historic center of Alba Iulia. 
