Fortress Reborn - Spectacular works at the Citadel

Excitingly, the gigantic renovation of the Citadel is already in its final stages in some areas. New planting has begun to create a greener and freer citadel. Flowering ornamental trees and shrubs are being planted to enhance the renewed fortress in all seasons.

The project will see the planting of more than 10,000 shrubs, 100,000 perennials and more than half a million bulbs, in addition to 128 large trees.

In addition to the panoramic view from the Citadel, a huge park and a unique architectural exhibition space will make the top of Gellért Hill an impressive meeting point for the city.

The extensive renovation of the Citadel and the Statue of Liberty is part of the effort to make the Danube bank landscape, which is on the World Heritage List UNESCO, including the historic Buda Castle and the historic Buda Castle Garden on the Buda side, worthy of this title in every respect.

Three monarchs admired the two hills of Gellért Hill

Built in 1854, the fortress has deteriorated badly in recent decades due to neglect and earlier unprofessional interventions. Zoltán Kromer, the ZÁÉV site manager, helped to guide the 170-year-old citadel's revival project, which began in 2020 with archaeological excavations. In the first phase of the works, one of the main tasks was the excavation of the masonry and slabs in the rondella, the western gun turret building. At the same time, work began on the reconstruction of the exterior walls and the interior courtyard.

The condition survey and the archaeological excavations were also a surprise. A World War I anti-aircraft gun emplacement was found, as well as Celtic and Roman ceramics and medals. The remains of the former observatory, built between 1813-17, were also found. The "two-humped", as it was colloquially known, served as the zero point of Hungarian cartography.

The importance of the scientific facility at the time was indicated by the fact that it was visited by the King of Prussia and the Russian Tsar, accompanied by the Austrian Emperor, who came to Hungary from the Congress of the Holy Alliance in Vienna.
The observatory was severely damaged during the siege of Buda during the 1848-49 Revolution and War of Independence, when the Austrian guards were shot from Gellért Hill by the defenders of the Austro-Hungarian army.

Decision taken on the demolition of the Citadel

The Citadel was built between 1850-54, after the defeat of the 1848-49 Hungarian War of Independence in an Austro-Russian alliance. The stones for the construction were quarried by the prisoner soldiers.

The "Bastille" on the Gellért Hill was a symbol of Austrian oppression and was a place of public worship. It was common in Pest-Buda that the 60 guns of the fortress were placed by the Austrians on a single high-priority target. In fact, the fortress was built as part of the fortification system protecting Buda Castle, with its turret facing west instead of Pest. Despite this, one of the main aspirations of Hungarian sovereignty was the acquisition and demolition of the Citadel. In the 1890s, there was a commitment by the prime minister and the mayor to do the latter.

In 1897, the Austrians symbolically handed over the keys to the Citadel, but were unable to relocate the soldiers, so they only left two years later. By that time, the demolition of the fortress was already enshrined in law. In the end, only a 67-metre section of wall was dismantled and gates opened on the hated structure.

Throughout its long history, the fortress has served as both an emergency shelter and a slum. None of the ambitious plans for its reuse were realised, and in the late 1920s it became a barracks again. During the Second World War, the fort was used as a prison camp, a bunker and the headquarters of a German division. In 1947, the liberation monument of Zsigmond Strobl Kisfaludi was placed on the hilltop.

History and its storms have left deep scars on the Citadel. During the renovation of the defensive walls, experts were confronted not only with the traces of the former bullet holes, said Zoltán Kromer, but also with the fact that some sections of the walls had been weakened by recent - unprofessional - restoration work. These were demolished and then rebuilt.

After re-carving, efforts were made to rebuild the original stones

The fortress walls were built with stones from the limestone quarry at Süttő. The structure of the walls had begun to weather over large areas due to moisture, salt loading and previous unprofessional repairs, resulting in a loss of strength in some sections. Zoltán Kromer said that the restoration work involved cleaning the surfaces and removing calcite and gypsum precipitates.

13800 m2 of walls were cleaned using sandblasting technology. In addition to removing moisture from the soil, a temporary salt-binding plaster was applied to the walls, which was later removed. In addition to repairing surface damage, stone elements were replaced where major damage had occurred. Efforts were made to reinstate, as far as possible, the stones that had been highlighted after the re-carving. The Tardos red limestone capstones on the ramparts were also restored and, where necessary, repointed.

The project manager of ZÁÉV added that the works are being carried out in phases, also to optimise scaffolding costs, with the reconstruction starting on the north side of the rondelle. Currently, it is 70 percent complete, with restoration and patination work on the outside and inside of the ramparts, and a 78-metre section still to be completed. The challenge is that the temperature of the wall surface must be above 5 degrees Celsius for the technology used in the restoration to be effective. The last part of the fortress wall to be renovated is 3,000 square metres, and more than 1,600 square metres of the surface have been desalinated.

7500 kilograms of steel on a dolomite rock - Flag waving at the site of the observatory

In 2022, during the winter, the 72-square-metre structure supporting the national flag was completed in just three months. On the site of the former observatory, the steel flagpole, 36.3 metres high and weighing 7.5 tonnes, was placed in a reinforced concrete block base on a bed of dolomite rock. A temporary transformer station was set up for its operation, and the national flag was hoisted on 15 March at the Citadel.

During this phase, excavations were also carried out next to the existing wall structures, near the rock face and at the foundation plane of the walls, which preceded the intersection of the walls in three places - north, south and east.

Cut through the wall of power

In the third major phase, a new entrance was built at the bastion behind the Statue of Liberty and connected to the inner courtyard by an impressive staircase. Zoltán Kromer said that the walls were opened up in three places in total, with new entry points created at the northern and southern mouths of the rondella, in addition to the eastern bastion. The operation was carried out in mechanical and manual phases, supervised by a specialist restorer. The surface area of the parapet walls affected by the demolition was 2140 square metres. The aim of cutting through the walls is to make the previously closed fortress more open and easily accessible to all. The Citadel will therefore be accessible from three directions instead of one.

The project also includes major construction work on the 4,280 square metre net floor area of the rondella building. The new reception area of the rondella is a rare architectural solution, with a glass support structure and a glass envelope.

In preparation for this, the construction of the supporting structures of the rondella was also launched during the same cycle and completed in autumn 2024. The elevator shaft of the main staircase was also completed at this time. The scale of the works is reflected in the fact that 5,000 cubic metres of concrete were used in the construction of the structures. 

At the moment, Zoltán Kromer said, the specialists are working on the cannon turret, doing the specialist work - building services and electrical work. The windows are in place and drywalling and plasterboarding have also begun in the part of the building that will house the future exhibition.

The glass bridge is made of 14-metre span elements

The creation of the exciting glass structures of the new exhibition hall's reception building, which presents the struggles for Hungarian freedom, is not an unusual architectural task. In the lobby, a special glass bridge and a glass spectacle lift have been built. Project manager ZÁÉV said,

In sixty days, eight glued glass beams, each 14 metres long, were installed. In addition, 14 glass walls measuring 11.2×2.4 metres per element were erected in place.

The design of the slab is also in line with the rest of the space, with seven glass elements, each 14.2 x 2.4 metres, installed to enclose the reception area. After the structural alterations to the north and south wings, the interior restoration work is well under way, followed by the cladding and painting work in the spring.

Strictly controlled straws

The Citadella's inner courtyard has also been extensively renovated, and the sewerage system has been completed. After the landscaping and gardens, they are now working on the 1,800 square metres of paving. Two kilometres of irrigation lines will help to maintain the new garden and green areas. The area has been filled with 2,500 cubic metres of topsoil and sixty trees will be planted. The Gellért Hill is a NATURA 2000 protected area, and the excavated soil and the soil transported to the site can only be used after it has been certified by an inspection.

14 thousand cubic metres of rock and earth shift on the mountain top

Half of the work is still to be done on the utilities. A major task is the construction of the pipeline networks in the rocky soil: the backbone cables are laid under the base plates, i.e. they are cut into the rock. The construction on the top of the mountain is also a challenge because of the site conditions and the slope of the slopes, and the laying of the cables at the planned levels is a challenge.

The project will renew the entire road and utility network of the promenade, including 700 metres of individual steel railings along the walkway. The paving work will involve moving around 14,000 cubic metres of rock and earth.

The parapet and staircase are given their final shape with huge white exposed concrete elements

The intersections of the auditorium and the protective walls were covered with white concrete. The elements, which weigh between 1.1 and 2.2 tonnes, are lifted into place using 80-150 tonne cranes.

The project manager said that this is a highly concentrated and precise process, and the surfaces are given a special protective coating after installation. Part of the concept was to create large exposed concrete surfaces, where the pure roughness of the concrete is revealed.

The white concrete elements of the staircase and the parapet - explained the ZÁÉV specialist - were produced in the same quality as the concrete of the bridge structure, to make them resistant to weathering and environmental influences. The white concrete elements are placed on a stainless steel back structure. Each element has its own anchorage, a solution that allows the white concrete elements to be individually adjusted and positioned to give an imposing appearance.
In this phase of the work, even greater attention was paid to organisation: the concrete elements are delivered to the site in the order in which they are
constructed and are immediately installed.

Statue of Liberty renewed inside and out

In the process of restoring the sculpture, after the scaffolding was erected, the restorers examined the work. After diagnosing the damage, they cleaned its entire surface. Damage repair was followed by surface conservation and patination. The metal screw connections inside the sculpture were examined and replaced where accessible. This meant, in terms of numbers, that 12,000 cubic metres of scaffolding were installed, and the specialists restored 200 square metres of the sculpture's surface, replacing 7,000 screws.
The exhibition in the Citadel and the rondelle is scheduled for completion in 2026.