The residential complex in Jazłowiec in Volhynia is one of the objects of secular architecture that was adapted for religious purposes. The palace remains both a memorial to the owners of the estate in the modern era and a centre of the cult initiated by Blessed Marcellina Darowska.

History of the Jazłowiec Estate
The history of Jazłowiec dates back to the Middle Ages. The most important owners of the estate were the Buczaczko family, who later adopted the surname Jazłowieccy and built a fortified upper castle. Significant urban and architectural transformations took place in the 17th century, when the estate was in the hands of the Koniecpolskis. The purchaser of the jazłowiec key was Stanisław Koniecpolski, Grand Hetman of the Crown, and the transaction was finalised in 1643. After the death of the leader (and one of the wealthiest magnates) in 1646, the development of the centre was taken care of by his son, Aleksander, who strengthened the fortifications of the town, which was struggling against Turkish invasions, among other things. Among the Koniecpolskis' architectural initiatives, the transformation of the residence stands out - the works probably concerned the old residence (the upper castle) as well as the new, neighbouring part of the development, known as the lower castle. However, the real flourishing of the residential complex took place in the next century.

The 18th-century residence of the Poniatowskis
. The creation of the three-winged palace was connected with the founding activity of the royal father, Stanisław Poniatowski, who purchased the jazłowiec estate in 1746. A U-shaped residence was built on the site of the lower castle. The building has two storeys, with the exception of the central part, which is raised by an additional floor and has three central axes each of the courtyard and garden. The architectural form of the palace is rather modest, with no articulation, and the main accents are the elements introduced on the axis in both elevations of the body: triangular pediments with heraldic decoration in the tympanum fields and stone portals leading to the passage gate. The setting of the entrance remains all the more interesting as it dates from an earlier period and may have been transferred from the former castle of the Koniecpolskis. The 17th-century garden portal is in Mannerist style, with anthropomorphic motifs (masks) in the frieze and on the pedestals of the columns flanking the gate, and ornamental decoration on the shafts. From the courtyard, the stone arcade is preceded by a portico supported by pillars. Behind the palace there was probably a garden area.

Monastery Palace
. From 1863, the residence belonged to the Sisters of the Immaculate Conception of the Blessed Virgin Mary, thanks to whom urgent restoration work was carried out. The nuns took the valuable initiative of setting up an educational establishment for children and a grammar school with a boarding school for girls. The institution offered a high standard of education and at the same time was oriented towards the transmission of moral ideals, which were most fully formulated by the then Superior of the Order, Marcelina Darowska - the main aim was to teach faith, patriotism and also independent thinking.

Blessed Marcelina Darowska remains the most famous figure associated with Jazłowiec. Among her contributions (apart from the development of education), it is worth mentioning the efforts to erect a mausoleum for the members of the community. The efforts were successful, resulting in the creation of a tomb where the first burial took place on 31 August 1874. The form of the subterranean mausoleum (located in the monastery park, at the edge of the hill) is a conscious reference to the Roman catacombs. At the same time, architectural simplicity was preserved: the building was given a rectangular outline, functionally similar to a cruciform plan, with an altar niche on the axis. The tomb provides for 96 crypts, arranged in three rows. Of the artistic initiatives related to religious worship undertaken by Mother Darowska, the commissioning in 1882 of a neo-classical statue of Our Lady of Jazłowiec is also noteworthy. The sculpture was cast in the Eternal City by Tomasz Oskar Sosnowski, a professor at Rome's Academy of Saint Luke. The artist used precious Carrara marble for the work. The Marian image was held in high esteem, which was evidenced, among other things, by the local regiment of uhlans entrusting themselves to the protection of Our Lady of Yazdlowitzka.

The Immaculata managed the palace complex until 1946, when they had to leave the monastery, moving to Poland - to Szymanów - and taking the statue of Mary with them. Later, the former residence of the Poniatowskis was adapted as a sanatorium for tuberculosis patients. An important moment in the history of Jazłowiec was the return of the sisters, who regained half of the residence and began efforts to preserve the memory of the place's past and to revive religious life.