Kazan Kremlin was originally constructed by the
Volga Bulgars in the 10th century AD. Kazan Kremlin was probably a wooden
fortress that protected a small settlement. Its remains were not
discovered. The first stone walls were erected in the 12th
century, although parts of the defences remained made of strong
oak beams. Mongols that conquered these lands improved the
defences and increased its size in 14th and 15th centuries. Most
of the castle walls were badly damaged in 1552 during Russian
siege. It was reconstructed by the stone masons from Pskov in
the second half of the 16th century entirely from bricks.
Originally the castle had 13 towers as a defence (some reached a
height of 58 meters), but only 8 of these survived today. City
walls reach a height of 12 meters.