The oldest extant Christian temple in the City of Grodno is St Boris and St Gleb’s Church, commonly referred to as Kalozhskaya Church as it was built in a sacred pagan settlement called Kolozhan.

Built in 1180 on a steep bank of the River Neman the unique church had survived intact until April 2 1853, when the southern wall of the temple collapsed as a result of a landslide triggered by the spring floods.

Kalozhskaya Church is the only surviving ancient Black Ruthenian architecture monument that stands apart from other Orthodox churches due to a prolific use of polychrome faceted stones of blue, green or red tint which could be arranged so as to form crosses or other figures on the walls. The church is a cross-domed building supported by six circular pillars. The exterior is articulated with projecting pilasters, which have rounded corners, as does the building itself. The ante-nave contains a choir loft, accessed by a narrow gradatory in the western wall. Two other staircases were discovered in the walls of the side apses, their purpose not clear. The floor is lined with ceramic tiles forming decorative patterns. The interior was lined with innumerable built-in pitchers, which usually serve in Eastern Orthodox churches as resonators. For this reason, the central nave has never been painted.

During restoration works, some fragments of 12^th―century frescoes were discovered in the apses.

Since 1991 the danger of recurrent landslides has been increasing, so it was decided to fortify the bank on which the church rests. Luckily, while shuffling the dusty archives, historians found detailed descriptions of the southern wall devoured by the landslide in 1853. Now they are busy developing a project to recreate the missing parts of the church to make it look their way it had been before 1853.

The church is currently on the waiting list to be included into the UNESCO World Heritage Register.