The ancient SS. Boris and Gleb (Kalozhskaya) Church in the city of Hrodna is a monument of the old Russian architecture and represents the Hrodna school of architecture. It was built in 1180s by the architect Pyotr Milaneh on the high right bank of the river Nieman, opposite to the Castle Hill, on the lands of the former Kalozhsky settlement. In the 16-17th centuries it was being restored, in 1853 it was partially destroyed by a landslide, in 1889 the southern apse collapsed. In 1910 and in 1935 conservation works were undertaken, and in 1970, 1985-1987 conservation and repair works were carried out. Preserved are the southern wall and a part of the western wall, as well as 3 apses, and 2 western under-cupola pillars.

The materials used in constructing the temple were brick, stone, glaze, and lime mortar. The church was a building sized 13.5x 21.5 metres, with three semicircular altar apses at the eastern side. The wall thickness was about 1.2 metres. The walls were made of thin plinths sized 3.5-4x16.5x26-28 centimetres. On the ends of some bricks there are Slavonic letters and bas-relief signs whose meaning has not yet been fully understood. The rows of plinths alternate with thick lime mortar seams with added finely ground brick and coal. The foundation of the temple is 1.5 metres deep and it consists of earth or sand-covered boulders. A short step-like pedestal formed the lower part of the church.

The brickwork of the façade walls includes large coloured, face polished, granite and gneiss stones, and figured glaze-covered ceramic tiles of various sizes, shapes and colours, which form various geometrical figures and crosses.

The church had three entrances: the central (on the western part) and two lateral ones. It was crowned by a cylindrical cupola. The upper part of the temple had arched windows. One cannot describe accurately the original outside view of the Kalozhsky temple: neither its upper parts nor the southern wall with parts of the adjacent walls fallen into the Nieman are preserved.

The main element of the interior decoration was the majolica floor made of diversiform plates of yellow, green, and brown colour.

The lower part of the northern wall has numerous bays. Fragments of frescos were discovered in one of them, and in the altar.

Within the upper part of the wall there are horizontally buried resonators - clay jugs whose necks were exposed into the rooms.

Six pillars about 1.2 metres in diameter were dividing the church into three naves.

In the western part, over the entrance, there were choirs. A projection they rested on is preserved. Within the walls, there were passageway stairs leading to the choirs. One of the stairs, on the survived northern wall, is preserved.

Due to some of its distinctive features (the majolica floor, resonators, stone insertions, ceramic tile patterns), the temple had no analogues in the East Slavonic architecture of that period.

At present, the Kalozhsky church is an active place of worship.