St. Archangel Gabriel's Church site is located on the left bank of the river Nišava before the village Ostrovica. The road to it leads through rich vineyards planted on the cultivated slopes of the mountain Oblik. In this beautiful environment, there is a temple about which all the historical sources are absolutely silent. We do not know who built it, or when, during whose reign, it was erected. We also have no idea about the looks of this seemingly impressive structure.
THE BYZANTINE BASILICA IN OSTROVICA, ENTRANCE TO THE CRYPT
What is left of once monumental temple is only a rectangular base of what used to be the church walls. The east side of the rectangular is closed southwards by a still visible apse. On the north, there is a fully preserved underground room, now covered with earth and debris. It is completely built in bricks and semi-cylindrically vaulted. It can now be entered through a small arched opening, the archvolt of which is made by radially laid bricks. Its inside is filled with water to a certain extent. There is a belief among the people that it contains a spring whose water has a healing power. The material used for the building was Byzantine-formatted bricks and ashlar.
The St. Archangel Gabriel's church site is supposedly a Byzantine basilica with a crypt, and its presence in the Sićevačka Klisura Gorge confirms the historical continuity of this almost unknown resort of monks. The fact that it was erected above a spring of water leads to a conclusion that this church site cherished the institution of Agiasmos (agiasmos) - blessed water, through which the cult of water had continued to be honored in the Byzantine building industry.