Castle & fortressTransylvania

Alba Iulia Fortress: the star-shaped Alba Carolina Citadel

Alba Iulia Fortress, also called the Alba Carolina Citadel, is a seven-bastion star fortress in the centre of Alba Iulia, in Transylvania, Romania. Built by the Habsburgs between 1715 and 1738, it stands on the site of a Roman legionary camp and a medieval citadel, and it is one of the finest examples of Vauban-style fortification in the country.

To build this star-shaped citadel, a whole medieval town was pulled down and rebuilt elsewhere, while more than 20,000 serfs worked in two-week shifts.

WhereIn the centre of Alba Iulia, Alba County, Transylvania, Romania

TypeStar-shaped bastion fortress in the Vauban style, 1715–1738

Best forBaroque military architecture, Habsburg history and a walk along the ramparts and gates

Getting thereIn the town centre of Alba Iulia; the Roman site of Castrum Apulum lies at the same spot, and Câlnic Fortress is about 21 km away

The history of Alba Iulia Fortress

Long before the star-shaped walls, this hill was already fortified. A Roman legionary camp of the Legio XIII Gemina, known as Apulum, stood here from the early 2nd century, and in the 16th and 17th centuries a medieval citadel called Bălgrad occupied the same ground. The Habsburgs, who took Transylvania from the Ottomans in 1688, chose this place for their main fortress in the province once the Treaty of Karlowitz in 1699 and the Treaty of Passarowitz in 1718 ended Ottoman claims to it.

The project was inspired by Prince Eugene of Savoy, who brought the fortification systems of Vauban into the Habsburg Empire. Plans were approved in 1714, and between 1713 and 1715 about 140 hectares were cleared by demolishing the old medieval town, which was moved to the east of the fortress. The foundation stone of the Charles Bastion, dedicated to Emperor Charles VI, was laid on 4 November 1715. The citadel takes its name from him: Alba Carolina means Charles’s Alba.

The design is credited to the Italian architect Giovanni Morando Visconti, who led the works until his death from plague in 1717. Military engineers Josef de Quadri and Konrad von Weiss then carried them on until 1738. Italian masons and stonemasons did the building work, and a team of sculptors from Vienna under Johann König carved the statues and reliefs of the gates and bastions. More than 20,000 serfs from all over Transylvania did the heavy labour in two-week shifts, using brick made locally and stone brought from nearby quarries.

The result is an irregular heptagon with seven bastions, around 12 metres high, surrounded by three lines of defence. The walls are slightly sloped, built without bumps so that iron cannonballs would ricochet. The original plan, with four lines and an outlying fort on the Furcilor Hill, was never completed: after 1738 the Habsburg money went to fortresses nearer the Ottoman border, and about a tenth of the design stayed on paper.

The fortress did see fighting in 1849, when Hungarian troops under General Bem besieged it for three months; the townspeople sheltered in the inner ditches. In 2009 the city received 47.5 million lei for restoration and conservation, and in 2014 the star outline became the basis of the city’s logo. Today the citadel is a listed historic monument and one of the Seven Wonders of Romania.

Curiosities about Alba Iulia Fortress

The seven bastions are named Trinity (the largest), Saint Stephen, Eugene of Savoy, Saint Michael, Saint Charles, Saint Capistrano and Saint Elisabeth.
The walls were deliberately built without bumps and at a slight slant, so that cannonballs would bounce off.
The citadel takes its name from Emperor Charles VI, known as Carol VI in Romanian, who ruled when it was built.
The Trinitarian church built in 1719 inside the fortress is today the Bathyaneum library.
Two bastions of the old medieval citadel were reused in the new fortress and turned into gun platforms called cavaliers.
Its star shape was the model for the logo that Alba Iulia adopted for city branding in 2014.

Tours near Alba Iulia Fortress

Experiences in the area that you can book online with Viator:

Turda Salt Mine, Corvin Castle and Alba Fortress from Cluj

★ 4.9 (121 reviews) · 11 h

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Private Day Trip to Turda Salt Mine and Alba Carolina Fortress

★ 4.9 (34 reviews) · 8 h

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Exclusive Tour: Corvin Castle, Alba Iulia and traditional villages from Sibiu

★ 4.8 (34 reviews) · 6 h

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Turda salt mine, Rimetea village and Alba Iulia, from Cluj

★ 5 (11 reviews) · 8 h

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Visiting Alba Iulia Fortress: what to see

The fortress is in the centre of Alba Iulia, so the whole complex is easy to reach on foot from the town.
Look at the gates: their statues and reliefs, inspired by ancient heroes and by the Austro-Turkish wars, are in the Baroque style. The main one faces east.
Walk along the ramparts and the main axis between Gates III, IV, V and VI to see how the three lines of bastions, ravelins and ditches fit together.
Castrum Apulum, the Roman camp beneath the citadel, is on the same spot and fits well into the visit; Câlnic Fortress is about 21 km away.
Opening arrangements for particular buildings can change, so check the current opening hours before you go.

Opening hours, access and conditions can change. Check before you go.

Map: where Alba Iulia Fortress is

Map: © OpenStreetMap contributors

Photos of Alba Iulia Fortress

Questions

What is Alba Iulia Fortress?

It is a star-shaped bastion fortress in the centre of Alba Iulia, built by the Habsburgs between 1715 and 1738. It is also known as the Alba Carolina Citadel and follows Vauban’s fortification system.

Who built Alba Iulia Fortress?

The project was supported by Prince Eugene of Savoy and designed by the Italian architect Giovanni Morando Visconti. More than 20,000 serfs worked on it, and it was named for Emperor Charles VI.

What stood on the site before the fortress?

A Roman legionary camp of the Legio XIII Gemina (Apulum) and a medieval citadel known as Bălgrad. The old medieval town was pulled down to clear space and rebuilt to the east.

Why is Alba Iulia Fortress shaped like a star?

Its seven bastions form the typical star outline of Vauban-style fortresses. The sloping walls and layered lines of defence were made to resist artillery.

What was the 1849 siege of Alba Iulia Fortress?

In 1849 Hungarian troops under General Bem besieged the fortress for three months. The population was allowed to shelter in the inner ditches.

What can you see near Alba Iulia Fortress?

Castrum Apulum is on the same site, Câlnic Fortress is about 21 km away, Căpâlna Fortress about 27 km and Sarmizegetusa Regia about 53 km.