Within the archaeological research conducted within the Church of Saints Peter and Paul, located in the historical and cultural reserve "Old Lutsk," frescoes and Latin inscriptions have been examined.

"Among the frescoes, there is a depiction on the vault resembling the coat of arms of the Jesuit Brotherhood. It resembles a sun, with a cross in the center and three Latin letters: IHS, which abbreviates "Iesus Hominum Salvator" (Jesus Savior of Humanity)," as reported by the restoration group KARP Restorer.

They also added that archaeological research continues in the underground chambers, as there is speculation that the area of ​​this complex is significantly larger.

"The church has a remarkable architectural complex of two-tier underground chambers, located at a depth of 8 meters. They were built in the early 17th century with the support of the Jesuit fathers. The underground structures were used for cult, defensive, and economic purposes. These include 12 halls, including the lower church, sacristy, remote galleries and rooms, tomb, refectory, and burial halls, as well as a well and clock tower," as reported by KARP Restorer.

The Church of Saints Peter and Paul is a monument of national architectural significance, built between 1616 and 1646 according to the design of the Italian architect Giacomo Briano.