Celje Castle was once the largest fortification on Slovenian territory. The first fortified building on the site (a Romanesque palace) was built in the first half of the 13th century by the Counts of Heunburg from Carinthia on the stony outcrop on the western side of the ridge where the castle stands. It had five sides, or four plus the southern side, which was a natural defence. The first written records of the castle date back to between 1125 and 1137; it was probably built by Count Gunter. In the western section of the castle, there was a building with several floors. Remains of the walls of this palatium have survived. In the eastern section, there was an enclosed courtyard with large water reservoirs. The eastern wall, which protects the castle from its most exposed side, was around three metres thicker than the rest of the curtain wall. The wall was topped with a parapet and protected walkway. This was typical of Ministerialis castles of the time.
The first castle was probably burned and destroyed in the fighting between the Lords of Sanneck and the Lords of Auffenstein. The gateway was later moved from the northern side by freemen loyal to the Lords of Sanneck. They gave the castle a new curtain wall and reinforced this with a tower on the northern side, which guarded the entrance to the inner ward, sometime before 1300. The new wall reached from a natural cliff in the east to the remains of the earlier wall in the northeast. The entrance was moved to the southern side, where it still is today.
In 1333, the castle came into the possession of the Lords of Sanneck, who from 1341 onward were the Counts of Celje. They set about transforming the fortress into a comfortable living quarter and their official residence. Around 1400, they added a four-storey tower which was later called Frederick’s tower. On the eastern side of the courtyard, there was a tall, three-story residential tower, which is the best preserved section of the castle among the Frederick’s tower. The main residential building, which also had rooms for women, stood however in the western section of the castle. This part of the castle ends at the narrow outer ward and is in a state of disrepair. On the southern side of the palatium, there was a tower, known as Andrew’s tower, after the chapel on the ground floor, which was dedicated to Saint Andrew. In the Middle Ages, the castle walls were impenetrable; an attacker would have had to rely on starving the defenders into submission, but a hidden passageway led from the castle to a nearby granary. The Counts of Celje stopped living in the castle in this period, but they stationed a castellan with an armed entourage here.
During an earthquake in 1348, part of the Romanesque palace and the rock on which it stood were destroyed. The ruined section was rebuilt and relocated towards the bailey. In the 15th century, the outer ward was extended on the eastern side of the ridge as far as the rocky outcrop. Here, the wall connected with a powerful, five-sided tower. In the second half of the 16th century, the castle was once again renovated. The walls in the inner and outer wards were made taller, and the bailey was renovated. The modern sections of the walls feature Renaissance-era balistraria.
The first imperial caretaker, Krištof pl. Ungnad, was named in 1461. Celje Castle was not only the most important castle in Slovenia, but in the entire eastern Alps. It covered an area of almost 5500 m². Several new techniques were employed in the castle’s architectural development, which were the model for other castles in the region under Celje’s influence.
The castle began to fall into disrepair shortly after losing its strategic importance. During the renovation of the lower castle in 1748, the castle’s tiled roof was removed. When Count Gaisruck bought the castle in 1755, he removed the roof truss as well. The best stones were then re-used in the construction of the Novo Celje Mansion between Petrovče and Žalec. From this time onward, it was no longer possible to live in the castle, and it slowly turned into a complete ruin. The last residents left the site in 1795. In 1803, the farmer Andrej Gorišek bought the castle and began to use the site as a quarry.
In 1846, the governor of the Styria, Count Wickenburg, bought the ruins and donated them to the Styrian estates. In 1871, interest in the ruins began to take hold and in 1882 the Celje museum society began efforts to restore the castle, which continue to this day. During the time of the Kingdom of Yugoslavia, the authorities in Maribor left control over the ruins to the local municipality, which made great contributions to the castle's preservation. During World War II, the ruins were abandoned, but reconstruction efforts continued after the war. In the corners of the Friderikov stolp, cement blocks were used to replace missing stones. A proper parking lot was also created in front of the entrance to the castle. On the northern side, the wall was knocked through to create a new side entrance to meet a new route that had been built there.
Today Celje castle is a popular tourist attraction and several concerts and other events are held there annually.
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