Kazan Kremlin

The date of construction of Söyembikä Tower is uncertain. Some scholars date it to before the conquest of Kazan by Ivan the Terrible in 1552. Others put the date later; in the 17th or 18th centuries. (Source: Wikipedia)

The Annunciation Cathedral dates from 1561 to 1562. It has been reconstructed several times.

The Spassky tower was first built in 1556-1562. It has been developed and re-built several times over the years.

Qol Sharif Mosque is a new addition to the Kazan Kremlin. It was opened in 2005. It is the largest mosque in Europe. (Source: Wikipedia)

 

References:

Kazan Kremlin website (in English)

WIkipedia