Historical-Town Planning Ensemble Tvrda (Fort) in Osijek

Date of Submission: 01/02/2005
Criteria: (i)(iv)(vi)
Category: Cultural
Submitted by:
Ministry of Culture Directorate for the Protection of Cultural Heritage
Coordinates: N 45°35' E 18°40'
Ref.: 161

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The area round the confluence of the Drava and the Danube abounds in major natural resources. It is also an intersection of major transport routes and a key strategic point. This is the reason why it has always been an interesting site for settlement and why everybody sought control over it.

The right bank of the Drava, some twenty kilometres from its confluence with the Danube, was of particular importance because of the easy crossing at that point. The communication route ran from the pre-Alpine region along the right bank of the Drava and the Danube towards southeastern Europe, with a branching to central Europe at the same point. Therefore, not surprisingly settlements were established in the area already in prehistoric times. With minor interruptions, their continuity has been sustained to the present day.

The oldest so far discovered traces of settlements in the area of present-day Osijek date from the Neolithic.

Urban-type settlements proper in the area date from the Roman period. Ancient Mursa was granted the status of colony during the rule of Emperor Hadrian by 133 A.D. According to preserved sources, because of its advantageous position Mursa was a harmonious blend of military and civil structures. Its strategic importance was reflected in the military features of the town, and together with security promoted crafts and trade. The resulting prosperity promoted the development of culture and the arts, and further growth of the town.

Mursa was devastated round 380 by the Goths and definitively destroyed by the Huns in 441. The centre of Roman Mursa was about 1.5 km downstream (eastwards) of the later Baroque Fort, on the site of the present-day main square in the Lower Town.

As the great movement of peoples gradually came to an end, the Croats settled close to the ruins of ancient Mursa. According to discovered traces, the early mediaeval settlement developed upstream of the ruins of Mursa in the immediate vicinity of the later Baroque Fort.

As crafts and trade began to flourish again in Europe in the High Middle Ages, urban life was also revived. Many old towns, Osijek included, were rebuilt in the period.

The new name of Osijek first appeared in 1196. As of the mid-twelfth century Osijek became an important and well-known market town on an important route. The centre of mediaeval Osijek was situated at the most advantageous point – the site of the later Baroque Fort. Testimonies to the mediaeval town include the excavated remains of the Romanesque church of the Holy Trinity, found on the site of the present-day Franciscan church.

During the rule of the Korogyi family after the second half of the twelfth century Osijek was a major traffic, business and administrative centre.

The Turks took Osijek in 1526 and ruled it until 1687. They did not change the layout substantially, but the public buildings and Islamic places of worship gave the town a completely oriental appearance.

The traffic and strategic importance of Osijek was sustained during Ottoman rule. At the time Osijek was known internationally because of the Suleiman Bridge, one of the world construction wonders as it was called, built during the rule of Suleiman II. The bridge, actually a wooden road on piers, was about 7 kilometres long and 6 metres wide. It connected Osijek and Darda, and it was burnt down by the Austrian army in 1686.

When the Austrian army defeated the Ottoman army at Haršanj/Harsany on September 12, 1687, the Turks panicked and fled Osijek.

The appearance of Turkish Osijek after the imperial army entered the town is shown in Beaulaincourt’s 1688 plan. The plan was drafted in order to reinforce the town walls, but as no changes were foreseen within them it faithfully reproduced the appearance of the town. It was basically oriental and distinguished by gradual, uncontrolled and unplanned development, particularly regarding the absence of space for squares. Such an appearance did not match the requirements of military and civil life, and Beaulaincourt’s plan was therefore discarded as inadequate.

The military administration paid increasing attention to Osijek as more and more people moved into the town. The plans for the construction of the fortifications and the development of the inner town underwent frequent changes and involved several military engineers. The construction of the hornwork, powder-magazines, bulwarks, the ravelin, ditches and trenches went on all the time.

The drafting of the final plan was entrusted to a military engineer, colonel Maximilian Count Gosseau de Henef. Unlike the many European builders of fortifications influenced by the famous French fortification builder Vauban, Gosseau had to tackle quite a few problems. He owed his renown to their solution which distinguished the Osijek Fort as a specific ensemble from other fortifications of the time. While builders like Matija Gambon in Karlovac or Giulio Savorgnani in Palmanova could freely develop an ideal town in free space, Gosseau had to face a number of constraints: he had to work fast because of the still present Turkish peril; when he took over design construction activities were already in full swing; the greater part of the population had to be moved to a line-of-fire distance from the fortification, while accommodation had to be provided for a number of citizens servicing the military within the structure; the old, totally uncontrolled and unplanned nucleus dating from the period of Turkish rule had to be totally changed, and a meaningfully planned and organized settlement developed; finally, he had to produce a curtain wall meeting high quality and technical standards.

Gosseau dealt with all these problems in a highly ingenious manner. The area of the inner town was bounded by a massive curtain wall, five bastions and the hornwork. The outwork on the left bank of the Drava was intended to protect the Fort from the north and serve as a bridgehead. Ditches with escarpments and counter escarpments surrounded the fortification along with “wolf’s teeth” and the glacis to the line-of-fire range. The walls themselves underwent later a change. According to Gosseau’s design, the outwork on the left bank of the Drava was to ensure sufficient security for the northern wall, but later on three additional bastions were built there.

Gosseau’s genius is particularly evident in the internal design of the Fort. By using a regular and rectangular street grid he achieved an excellent layout and communication. He set apart free areas for squares and provided a good arrangement of blocks. He accurately specified the blocks to be used for military buildings (mainly close to the curtain wall), for civil buildings and for mixed buildings. He also intuitively left some unbuilt areas, to be used later for military facilities. Gosseau’s design within the Fort was consistently respected during construction. The area of the former mosques was left for the churches. In the limited area within the walls Gosseau was able to achieve a perfect harmony of military, civil and ecclesiastical life.

Even the ingenious Gosseau could not foresee subsequent developments: the Fort soon became an administrative, educational, cultural and scientific centre, too.

Apart from the Osijek Fort, in the late Baroque and classicist periods there are no other examples of a fortification condensing overall military, civil, administrative, ecclesiastical, educational, scientific and cultural life. This enhances its significance and specific character.

In his book The Town Planning Development and the Monumental Significance of the Osijek Fort Dr. Ive Mažuran, long-time researcher and journalist, the leading expert on the Osijek Fort, commented Gosseau’s accomplishment: “Similarly, by subordinating the overall spatial solutions to the functions of the military fortification Gosseau was aware that he was completing the final stage of the town’s development by building a huge curtain wall round it. In this regard, his approach to the construction of the Fort and to the design of the existing urban settlement on a fully defined spatial basis represents an outstanding achievement and a unique phenomenon not only in this country but also on the European scale.

Namely, in putting his ideas to practice Gosseau succeeded in building a military and urban monument distinguished by unity of time and space. There are no similar structures in Slavonija in particular and Croatia and general because the forts in Slavonski Brod and Nova Gradiška are exclusively military structures with no urban nuclei. The military fort in Petrovaradin does not bear comparison with Osijek either. This enhances even more the identity of the urban nucleus within the Osijek Fort in comparison with other ensembles, and its great monumental value deriving from the specific conditions of its development. Ultimately, this means that it contains its own sources of cultural, urban, monumental and other value yardsticks”. Furthermore, says Dr. Mažuran, “I have seen many European towns, but have never found an identical development whereby an existing urban nucleus was turned into a fortification, or a similar town-planning solution”.

Gosseau’s plan was accepted and construction started on August 1, 1712 under the supervision of general Beckers. The work was also closely monitored by the inspectors of the Court Chamber and the Military Council in Vienna.

By 1715 all the five planned bastions were completed along with two gates – the northern Vodena Vrata (Water Gate) and the southern Nova Vrata (New Gate) – in line with the basic envisioned line of communication. The most important routes of communication between the Fort and the outer world were the southern entrance which led to the cardo, the present-day Franjevacka Ulica (Franciscan Street), and the northern exit to the river Drava. The western Valpovacka Vrata (Valpovo Gate) leading to the Upper Town was completed the following year.

Barracks, an armoury and a powder-magazine were built within the fort walls, and the main guardhouse (Hauptwache) in the main square. The construction of the Outwork on the left bank of the Drava was completed by 1721.

The area of the inner town was also developed along with the construction of the fortifications. Streets, squares and blocks of buildings were built according to Gosseau’s ideas and in the spirit of Baroque town planning. The houses were built with materials of good quality (fired brick and stone) with tiled roof structures and masonry chimneys. Mainly multi-storey houses were built along the main streets and in the squares, and single-storey ones elsewhere. Business premises adjusted to the specific craft were available at the ground-storey of the former and within the structure of the latter. Some streets in the Fort were even named after artisans, e.g., Mesnicka Ulica (Butchers’ Stret), Staklarska Ulica (Glaziers’ Street), Tokarska Ulica (Turners’ Street), etc.

However. inn-keeping was the leading business in the Fort. The numerous officers and soldiers needed places where they could have a good time and relax. In the mid-eighteenth century there were more than thirty-five inns in the Fort, probably in one out of three buildings. Most of the inns faced the barracks. Nine civil buildings with seven inns – Crni Medvjed (Black Bear), Plavi Šaran (Blue Carp). Zlatni Lav (Golden Lion), Smedi Konji} (Brown Pony), Zeleni Križ (Green Cross), Zlatno Sidro (Golden Anchor) and Tri Potkove (Three Hoseshoes) – were built in the present-day Firingerova Ulica (Firinger Street) from Ulica D. Pinterovi} (D. Pinterovi} Street) to Franjevacka Ulica. The quality of service varied, but some of the establishments were of a high class. Thus, crown prince Joseph (future emperor Joseph II) resided at the Blue Carp when he visited Osijek.

The construction of the inner town was completed by 1733. Few free sites were left. The streets and squares obtained their final appearance preserved until the present day. The construction of the general barracks was completed at the northern side of the main square, and of the new guardhouse in its northwestern corner.

The widow of general Petraš had a statue of the Holy Trinity erected in the main Fort square in 1729. It is a typical example of the Baroque relation between sculpture and open urban spaces.

Three additional northern bastions were completed in 1735 along with the post office, the construction office and the relocated hospital. The major project in 1865 involved the addition of a storey to the general barracks.

The fortress was fully completed by the eighteen-sixties. It had eight bastions, two armouries, two major depots, the garrison headquarters building, the military court, the construction office, the garrison physician, the guardhouse, officer apartments, the military hospital and seven barracks.

Street lighting provided for the urban atmosphere of the Fort as early as since 1717. The water supply system was completed in the early eighteen-sixties, and the sewage system somewhat later.

Along with military and civil construction churches and monasteries were also built in the Fort. The Franciscans started to build their Baroque church in 1709 (until then they had used the converted mosque). The church was consecrated in 1732. The monastery was built earlier next to the former mosque, and subsequently enlarged. In 1730 the Franciscans exchanged with the military a house in the main square for a site south of the church, and built a new monastery there in the second half of the eighteenth century. The Franciscan monastery was not merely a source of faith but also of culture, education and science. The first school was opened there and a course of studies and the first printing works established in 1735.

Like the Franciscans, the Jesuits also used a converted mosque for their church, and then built first a monastery. In 1725 they started to build the parish church of Sv. Mihovil (S. Michael) along the western wing of the monastery. Although still incomplete, the church was in official use after 1734. The former mosque was torn down, producing an irregular square in front of the church.

The period of enlightened absolutism brought about changes in military life and organization. More functional military facilities and better residences for high officers were built. The brigade headquarters in the Fort was completed in the late eighteenth century, followed by the garrison headquarters (combined in a single building with the Construction Office), and the general’s and town commander’s mansions.

Civil buildings were also modernized or enlarged. However, the scale of such projects was limited because permits for any changes had to be obtained not only from the military Construction Office in Osijek but also from its counterpart in Vienna. This is also the basic reason why the Fort has largely retained its authenticity.

The early nineteenth century was a period of major changes in the administration of Osijek. In 1786. Joseph II decreed the merger of the three town municipalities (the Upper Town, the Lower Town and the Fort) into a single town council, and in 1809 Osijek was granted the status of a free and royal town. The town council was accommodated in the building of the former Fort Municipality at the south-eastern corner of the main square.

No major construction took place within the Fort up to the nineteen-seventies. The new military structure involved certain construction projects as well. A large and spacious barracks was built along the south wall, and a depot, guardhouse and the garrison prison by the western entrance. The old barracks building in front of the eastern gate was torn down and a new one built by the large armoury. The sixth and the seventh bastions on the left bank for the Drava were also demolished in the same period.

As political and military conditions in south-eastern Europe calmed down after the Berlin Congress in 1878, the military importance of the Osijek Fort waned. Military engineers no longer strictly controlled construction and reconstruction within the Fort. The Fort was even earlier the educational centre of Osijek, and new changes also brought about the construction of new school buildings.

The construction of the Royal Grammar School started in 1881 in the former Solni trg (Salt Square); at the corner of Markoviceva Ulica (Markovic Street) and Firingerova Ulica (Firinger Street) three houses and part of the Drawing School were brought down in order to make way for the Royal General Secondary School completed in 1890. The Episcopal seminary was built in 1898 at the south-western corner of the main square and Kuhaceva Ulica (Kuhac Street). All the three structures were built in line with the historic and eclectic spirit of the time.

The development of urban life and the growing requirements of the inhabitants of the Fort called for certain changes on residential buildings. They mainly involved minor reconstruction or additional construction. Owing to the wear of time, the repair of building fronts and roofs became necessary, resulting in historic or eclectic facades on the originally Baroque buildings in the Fort. In time the military fortifications lost their basic function, and their expensive and complex maintenance posed a major burden for the military authorities. The Fort also hindered further development of the town. Its walls prevented an efficient and fast connection of the Upper and the Lower Town. The administration of the town called for the removal of the walls bearing in mind only the traffic and business requirements and not monumental value considerations.

All these reasons and the planned construction of the electric tramway speeded up the decision on the demolition of the walls. It was started in 1923 and completed in 1926. Out of the former large-scale fortress walls only parts of the first and the eighth bastion were preserved along with the northern wall and the Water Gate in between. The Outwork on the left bank of the Drava was also torn down. Fortunately, the bared nucleus of the Baroque Fort was not touched and has been preserved with slight changes to the present day.