Gliwice was surrounded by defensive walls in the first half of the 14th century. During the Hussite wars, the Taborites captured and plundered Gliwice, making the city a starting point for their armed expeditions. In 1431 duke Konrad the White recapture the city, wherein a significant part of the inhabitants were murdered or imprisoned, and fortifications were destroyed to a large extent. After the Hussite wars, the fortification system required reconstruction. At the end of the 18th century and throughout the nineteenth century, their gradual demolition and liquidation took place.
Castle in Gliwice was most probably built along with the city walls in the mid-fourteenth century under the reign of Siemowit, the Bytom prince. It has not been located to this day. One can only assume that it was in the north – western corner of the city. The castle known today as Piast Castle in historical sources, has appeared in the 16th century as the Cetrycz Manor (Manor of Zetritzs), and for its construction a city wall and fortified towers were used. It was rebuilt in 1558-1561, by the then city’s leaseholder, Fryderyk von Cetrycz.
In the second half of the eighteenth century, the defensive walls were reduced to about 7 meters, which allowed for further reconstruction of the building. In the mid-19th century, in place of the demolished medieval tower, the new eastern wing of the building was created, modeled on the west wing.
Originally, the perimeter of the walls had 1125 meters, their height reached 8,5-9 meters, and the thickness was sometimes even up to 1,2 meter. The circumference was erected mostly in the opus emplectum technique with a brick face in the flemish bond. The foundations were erected mainly from glacial erratic stones. The use of different construction materials for building may suggest that walls were created in several stages.
Within the fortifications there were 29 (according to other sources 36) half towers and two four-story gate towers: White, also called Bytom Gate and Black, also called Racibórz Gate. The Black Gate from the outside was protected with an additional foregate. The towers had a rectangular shape with regular external dimensions of 2 x 8 meters and were originally mostly open from the inside. The exception was the towers absorbed by the castle and the tower at the Black Gate, which although built with the wall and clearly tied to it, were thicker by about 0.2 meter. Their height was probably slightly larger than the curtain and amounted to about 9 meters. The curtain had a porch for defenders. According to early modern urbariums in the seventeenth century, the fortifications consisted of a high earth embankment, acting as a bulwark, a moat away from the wall line about 7 – 12 meters and a slope with a wooden palisade behind which was a city wall.
The first stage of the castle construction consists of two towers connected with a curtain wall and a wooden gallery. In contrast to the majority of Gliwice towers created on the plan of the letter “U”, the castle towers were built on a square plan. At that time, they probably played the role of an arsenal. In the middle of the 16th century, a two-storey brick building with five windows axes was built between the towers. The ground floor and first floor of the western tower were also adapted. Mono-pitched roof was adjacent to the defensive wall. In the 18th century, the western tower was lowered, but enlarged along the north-south axis and rebuilt on a rectangular plan. The new wing was covered with a gable roof, similar to the space between towers.
To this day, fragments of medieval fortifications have survived, among them a curtain with a tower, which was used in the construction of the castle, and a fragment of the wall near the parish church of All Saints. Currently, the renovated castle buildings house a museum.
Leksykon zamków w Polsce, L.Kajzer, S.Kołodziejski, J.Salm, Warszawa 2003.
Sypek A., Sypek.R., Zamki i obiekty warowne od Opola do Żywca, Warszawa 2014.
Webpage skladnica gornoslaska.pl, Miasto Gliwice i mury obronne.