The St. Basil's Cathedral was commissioned by Tsar Ivan the Terrible in 1555 to commemorate the capture of Kazan, a small city held by the Tatars. The project was designed under the guidance of an architect named Postnik Yakovlev and built between 1555–1561; it was completed in 1561 and served as a church for nearly 400 years before becoming a museum in 1928.