The cathedral has unique decorations. There is also a well preserved, 25-meter, seven-tiered iconostasis which is the same age as the church. It is a unique creation that is brightly decorated with gilded carvings. The decorations, frescoes, stucco, bright colors and the detailed facade give the architectural monument its exceptional image. North-east of the cathedral, there is a 49-meter, six-tiered bell tower with baroque decor that is just as amazing as the rest. The Peter and Paul Cathedral has been the most visited church of Kazan throughout its history, leaving no indifferent visitors in Kazan. Many Russian emperors, famous writers, and public figures expressed their admiration for this church. The famous opera singer Feodor Chaliapin sang within the walls of the Peter and Paul Cathedral. Not to mention, one of the earliest descriptions of the cathedral is contained in the writings of Alexander von Humboldt and Alexander Dumas.