The Cathedral Mosque is the oldest building in Bolgar. The mosque in the city of Bolgar appeared during the time of Khan Batu. Construction began shortly after the Mongol conquest and was completed by the 1260s. Over its existence, it was destroyed several times and reconstructed twice. In the 13th century, the mosque was the main religious structure of the Bolgar ulus of the Golden Horde. It was a large fortified building with a strong foundation and stone walls. The mosque amazed with the beauty of its decoration and was visible even from a great distance. However, it existed in this form for only 50 years before being almost completely destroyed. In the 14th century, it was restored, but the mosque then acquired defensive functions — the wooden flooring was replaced with stone, and polygonal fortress towers were added.

The purpose of this majestic structure was to symbolize the greatness of Islam and embody the power of the state. The mosque was meant to astonish visiting travelers so that they would spread its fame throughout the world.

The central streets of the city originated from the temple. This was convenient for residents who gathered here at prayer times. The mosque’s shape was a rectangle measuring 32 by 34 meters. Inside, there were 12 columns. The building’s walls were made of stone. The floor and ceiling were made of wood. Constructing this grand structure required 1,200 tons of marble.

In the 1960s, the mosque was restored: the walls were treated with special solutions, the towers were covered with artificial blocks, and the floor was reinforced with a special coating. To this day, only the foundation, walls, and towers remain, along with a restored part of the ruins.

Today, the mosque survives only in ruins: fragments of walls rise above the ground, and the interior space is divided into stone squares that served as the bases for columns inside the mosque hall. Only the foundation and some wall elements have survived to the present day. But even these impress with their scale. By the way, the architecture of the Cathedral Mosque can be appreciated at the Museum of Bolgar Civilization, where a model of the building is exhibited. It is located nearby. The mosque had an almost square shape and was supported by quadrangular pillars; the ceilings were wooden, and the main entrance was located near the minaret.