Kazan Cathedral, Saint Petersburg - online puzzles

Kazan Cathedral or Kazanskiy Kafedralniy Sobor (Russian: Каза́нский кафедра́льный собо́р), also known as the Cathedral of Our Lady of Kazan, is a cathedral of the Russian Orthodox Church on the Nevsky Prospekt in Saint Petersburg. It is dedicated to Our Lady of Kazan, probably the most venerated icon in Russia.