The carthouse at Bereza, erected through the efforts of the Lithuanian sub-chancellor Kazimierz Leon Sapieha, was one of the richest monastic foundations of the former Commonwealth. Today, only ruins remain on its site.

The carthouse at Bereza was the only institution of this order built on the lands of the Grand Duchy of Lithuania and one of only three established within the borders of the Polish-Lithuanian Commonwealth. Today, only fragments of the walls remain on the site of the former hermitage. The remains of the complex are extremely picturesque, with the brick walls of the former farm buildings visible in the lush grassy area, partially surrounded by a wall with an entrance gate and towers in the corners. Overlooking the spacious square is the bell tower, originally situated behind the monastery choir of the church. Neither the church nor any of the fifteen hermitage cottages survived the turmoil of history, and less than half of the numerous buildings of the monastery farm remain in ruins. However, even these sad relics give an idea of the once monumental nature of the foundation.

Foundation of the Holy Cross Carthusia
The Carthusia was the most important, largest and most generously endowed religious foundation of the Lithuanian sub-chancellor Kazimierz Leon Sapieha (1609-1656), who in June 1648 brought to Bereza an Italian architect, probably the designer of the entire foundation. In accordance with the will of the founder, the crypts of the Carthusian church became the mausoleum of his family and the final resting place of several representatives of the Sapieha line of the Cherno-Rozhans. The connection of the Carthusian church to this family was highlighted in a spectacular way - on the top of the helmet of each corner tower, on the buildings and the well, as well as above the entrance gate, there was a magnificent "Fox" coat of arms, visible from afar.

Due to the political situation of the Republic at the time, the church and its buildings were surrounded by a fortified wall. They decided on a traditional fortification system with five powerful octagonal towers, with ramparts and a moat. Within the walls, in addition to the church and monastery buildings and numerous outbuildings, there was also a pond where the monks kept turtles (according to the strict Carthusian rule, the Carthusians did not eat meat, but sometimes turtles and beavers, as aquatic animals, found their way onto their tables).

Construction work on the Carthusian site stretched over several decades, and took a particularly long time on the longest, economic north wing. Evidence of the completion of the construction appears to be the annual date '1689', placed in the field of the semi-circular abutment of the gate leading into the courtyard of the monastery. One of the archival descriptions of this gate included information about a 'whale's jaw hanging on iron hooks'. It is not known whether this was actually a fragment of a large marine mammal or another large animal, but in any case it probably acted as a kind of amulet to protect the inhabitants of the carthouse. This was not an isolated case; such 'curiosities' occurred at the time in both monasteries and churches.

Further history
The heyday of the Carthusians, which lasted less than a century and a half, was followed by four decades of slow decline, culminating in the cassation of the institution. After the third partition of the Republic of Poland, contacts with the monastic authorities ceased, the monastery lost its wealthy patrons, and the subsequent turmoil of history undermined not only the economic foundations of the institution, but reportedly also the moral condition of the monks themselves. Eventually, the Domus Sanctae Crucis was liquidated by a tsarist decree of 28 August 1831, which officially followed the monks' involvement in the November Uprising. It was then decided that the monastery church should become the parish centre of the Pruzhany deanery, while the other Pokartusk buildings were placed at the disposal of the army. The last monks left Bereza in 1834, sent to the Benedictine Abbey in Horodyszcz near Pinsk.

From the 1860s, the systematic demolition of the former Carthusian monastery began. Materials from the demolished monastery buildings and church were used to build a complex of barracks for the army, which in the 1920s was occupied by the School of Infantry Reserve Cadets. On the basis of a decree of the President of the Republic of Poland of 17 June 1934, it was in these barracks that a place of detention was established, where persons considered dangerous to state order were held. By September 1939, almost ten thousand prisoners were incarcerated there, causing the name Bereza Kartuska to become widely associated with more than just the Carthusian monastery.

Memory of the Carthusians
It is regrettable that on the vast grounds of the former eremitic foundation, which was inhabited by the "silent monks" for two centuries, there are now only crumbling ruins. The site during its heyday is vividly described in numerous archives - in one of which an 18th-century visitator noted: "The carthouse is of great shape, whether you look at the outbuildings, or at the carefully crafted ornamentation of the church and bell-tower, or at the houses of the monks, or at the double ring of walls with which it is surrounded both for beauty and for defence, in the manner of a fortified fortress". In the 1980s and 1990s, excavations were carried out on the monastery grounds - Belarusian archaeologists found, among other things, numerous kitchen utensils, fragments of decorated ceramic tiles and glassware made in the manufactories of Antoni Tyzenhaus and the Radziwiłłs, now enriching the exhibition of the Bereza History and History Museum. The entrance gate has recently been renovated, looking rather bizarre against the background of deteriorating fragments of walls and walls.