Cetatea Alba Carolina - Arhitectura


Date of construction:

The architecture of the bastionary citadel of Alba Iulia obviously includes the main characteristics of the Vauban-type fortifications, a system elaborated by the French military engineer Sébastien Vauban Le Preste (1633-1707). Considered a "genius of fortifications", Vauban knew how to sum up all the important findings in the field of fortifications that came about until his time, making a most inspired combination between the ingenuity and the architectural creations of the Italian bastionary school and the precision of the proportions and the complementary elements of the bastionary system in the Netherlands and Germany.

General Eugeniu de Savoia promoted the generalization of the Vauban system in Transylvania at the beginning of the 18th century and was also a supporter of the construction project of the Alba Iulia citadel, a document elaborated by the Italian architect Giovanni Morando Visconti.

The citadel of Alba Iulia represents the best example of the Vauban type in Romania, enduring over time, remaining the largest bastionary citadel still standing in Romania and one of the largest in Southeastern Europe. Also, it remains a work of art illustrating the bastionary fortification system due to the fact that the works performed here are remarkable, the line of the walls, the alignments, the bastions, the crests, the foundation, but most all the gates prove the craftsmanship of the masters who worked here.


The defense components


The bastions

Seven large bastions connected between them with walls of the same height, form a "safety precinct" in the central area of the fortress, this being the most important area and the best protected. Known as the magistral or the main body of the fortification, this curtain wall was designed to adapt to the irregularities of the terrain, shaped as a seven-cornered start (a heptagon), a configuration which can also be observed in the other exterior defense lines (the ravelins and the counterguard). At the time they were built (1736), the bastions received special names which were connected to the laic or religious patrons (starting with Gate III towards the left, in a clockwise direction): Eugeniu of Savoia bastion, Steinville bastion (later Saint Stephen bastion), Trinity bastion, Saint Michael bastion, Saint Carlo Borromeo bastion (Carol), Saint Elisabeth bastion, Saint Capistrano bastion (later the Transylvania bastion).

Built out of bricks and earth fill, the bastions have approximately the same dimensions, the length of the sides ranging from 110 to 120 meters and the medium height between 10 and 12 meters. The bastions are triangular in shape, their tips oriented towards the exterior. The connection with the curtain wall, which links them, is made by means of the rounded extremities of the sides (the ears) and the flanks arched towards the interior (the neck). Artillery holes were placed above the bastions, on each of the two flanks, well protected by their location behind the guard wall. Then the rammed earth followed, a terrace on which defense troops could walk on, sheltered from the enemy projectiles. It was located 3 meters under the crest of the guard wall and about 5 meters wide, offering sufficient space for the moving of the troops and for the maneuvering of artillery items. The access from the rammed earth to the artillery or infantry barracks was made through a downgrade with a gentle slope. In some cases, in order to place the artillery in a dominant position and with the goal of obtaining an efficient observation point, additional works used to be performed in the central area above the bastion, to heighten the bastions’ or chivalry’ reduits. In the case of the Eugeniu de Savoia bastion and the Saint Stephan bastion, the purpose of these constructions was fulfilled by the old bastions of the medieval fortress, erected during the time of prince Gabriel Bethlen. The crests of the bastions were adorned with statues placed on pentagonal stone platforms, under which there existed figurative sculptural groups, coats of arms and inscriptions playing the role of console. Similar platforms were also found in the bastions’ flanks, above the ears, but these were meant to host the watch house where the guard served. The brick curtain wall between the bastions measuring 100 m in length presented the same particulars encountered in the construction of bastions and that is an inclination of 80°, by a gradual decrease of dimensions, from base to top (from 2.50 m to 2 m) with the purpose of absorbing the pressure of the great volume of earth. Moreover, the inclined walls were built with interior buttresses which had the same role of anchoring the exterior wall and stabilizing the earth fill behind these.



The ravelins or the crescents have similar shapes and dimensions with those of the bastions (length of sides 90 m), from which they also took the names, with a single exception (ravelin Saint Francisc of Paula). Their main role is to defend the works behind (the safe precinct), being placed in front of the bastions where they are located in the clear interval between the overhangs. Together with the counterguard, they represent the category of exterior works, designated to form the battle precincts. In order to offer the magistral or the fortification body a good command of the ravelins (the dominant position) and the protection of bulwarks, the sides have an inward slope, a characteristic encountered in all fortification elements. Six meter high reduits were built on two of the ravelins – Saint Carol and Saint Elisabeth, similar to those of bastions, these works allowing the bulwarks to stand even when the ravelin is conquered.


The pliers

Unlike other Vauban-type fortifications, the citadel of Alba Iulia does not have bastions with inner casemates, the defense of the flanks being achieved by means of pliers (tenailles), placed two-by-two in the interval between bastions. The pliers together with the ravelins, the ravelins redoubt and the counterguard are part of the category of outside works meant to protect the magistral or the main body of the fortifications (the bastions and the curtain wall which unites them). The pliers erect in the moat, under the form of two islands (earth and masonry masses), their reduced height (4 m) allowing the artillery situated on the bastion platforms to shoot between them. The distance between pliers (50 m) was set with the purpose of allowing the caponiere to pass between them.


The counterguard

After the bastions and the ravelins, the counterguard is the third and the last line of defense of the citadel, adopting the shape of a masonry and earth curtain wall. The counterguard jag follows the projected parts and inlets of the bastions, the ravelins, having the purpose of defending them and are usually placed in front of them. In the Southeastern and Northeastern parts, from the Steinville bastion to the Saint Elisabeth bastion, the counterguard reaches impressive dimensions (from 50 to 200 m wide), the terraces created on the remblai or the underground galleries allowing artillery items to be placed here and making it possible to protect the garrison. The counterguard on the entire length of this route received the name of envelope and it has a partially floodable ditch bordered by walls. In the Southwestern and Northwestern parts, the counterguard narrows down to 25 m width, prolonging in order to connect the ravelins between them or to protect the bastions in front of which they pass. The ditch in this area no longer has a counterscarp encased in masonry, and given the glacis is lacking, the scarp which supports the remblai of the counterguard reaches a height of 6 m.


The ditches

Each of defense elements – the bastions, the ravelins, the pliers, the counterguard – which form the lines of defense is preceded or confined by a ditch the dimensions of which are different in width rather than in depth, thus existing the possibility for these to communicate. More evident differences in level are only encountered in the Southeastern and Northeastern areas where the gradient is more accentuated. The main ditch or the large ditch in front of the fortification body is 25 m wide, the crescents are 15 meters wide, reaching 12 m in front of the counterguard.




The citadel gates

The entrance in the citadel is made through the six gates placed in equal numbers to the East and West, one on each defense line.

Built out of embossed stone blocks, the gates differentiate by the amplitude of their dimensions and by the complexity of their shapes, four of them displaying richly ornamented facades with embossments and statues.


The approach slope

Set up in the earth mass behind the walls under the shape of gentle slopes declivities with a width of 2-4 m, confined by rampants with or without pinnacles, their entrances protected by metallic grids, the approach slopes allowed the access of fighters and the moving of artillery items to the fortification elements: the bastions, the ravelins, the pliers and the counterguard.


The posterns

The posterns adopt the shape of an underground arched gallery, with an accentuated slope, allowing the communication of superior parts of the fortification body with the surrounding ditch. The entrance in the postern was situated at the base of bastion’s guard wall. From there one went down the wood or stone stairs, reaching the level of the ditch, behind the bastion’s ears. The gallery exits were blocked by doors or metallic grids through which one could shoot, sheltered in lateral niches. Another postern was created in the space between bastions, at the middle of each curtain wall, the entrance being situated at the base of the guard wall and the exit being found in the scarp wall, five meters above the ditch. The purpose of this horizontal underground gallery was to make the connection with the caponiere passage, by means of a mobile flight of wooden stairs which could swing out.


The caponiers

They are in the shape of a three meters wide passage or a covered gallery transversally crossing the large ditch (the fortification body ditch), accomplishing the connection between the curtain wall and the ravelins. This way, the citadel defenders would enter the postern which crossed the curtain guardrail, they would lower the mobile stairs in order to come in front of the caponiere which they crossed in safety up to the entrance created in the counterscarp of the ravelin. From here, by means of other ramifications of galleries existing in the body of the ravelin one arrived over it or in the ditch limiting it from the counterguard. The third fortification line – the counterguard or the envelope – was also crossed by arched galleries for circulation, storage rooms or shelters and casemates for artillery parts.