The iconostasis of the Annunciation Cathedral comprises about a hundred icons placed in six tiers, namely Veneration, Menaion, Deisis, Festive, Prophets and the Forefathers (from the bottom upwards). In ancient times there were more icons than nowadays, as a number of icons occupied a part of the north and south walls too. Now only the bottom tier is arranged in that way. A high and many-tier iconostasis has become a focus of Russian church from late 14th - early 15th century. The meaning of a high iconostasis, entirely hiding the altar from the congregation, is closely related to the process and texts of divine services and presents its pictorial interpretation. Icons of the Deisis and the Festive tier of the Annunciation Cathedral’s iconostasis are most ancient among extant ones. It has long been an accepted fact that these icons, made during the period when Russian culture flourished, that is the turn of the 14th-15th centuries, are key monuments of Moscow school of icon-painting.