The Cathedral of Ss Peter and Paul reflects Peter I’s interests in Western Europe. The appearance of the cathedral followed the early Baroque style as Trezzini executed Peter’s desires. In this, the design of the cathedral borrowed much from the protestant churches of western Europe, particularly Dutch architecture. The basic execution of Peter’s ideas was accomplished between 1722 and 1727 by a team of over forty architects from Moscow under the leadership of Ivan Zarudny that combined Lutheran architectural elements with icons painted in the Western style of the [[Roman Catholic]] church.
[[Image:P-PRoyDoorSP.JPG|right|thumb|200px|The Royal Doors of the Ss Peter and Paul Cathedral]]
Over the years the interior decoration has been refurbished often as temperature and humidity have been the enemy especially of the woodcarvings in the cathedral. The composition of the [[iconostasis]] frame by Trezzini, that he drew from the western European Baroque concepts, was implemented in Moscow by a team of woodcarvers under Ivan Zarudny, then shipped to St. Petersburg, and assembled in the cathedral. The arrangement of the figures ([[icon]]s) on the iconostasis was drawn up by Peter I and Archbishop of Novgorod, Theophanes Prokopovich. The set of forty three icons for the iconostasis was created by the Moscow iconographer A. Merkuryev (Pospelov) and his team. Ravished by the hard climate in St. Petersburg, the wooden Royal Doors were replaced in 1866 with exact copies that were cast in bronze and then gilded.
[[Image:P-PCathPulpitSP.JPG|left|thumb|150px|The pulpit in the Ss Peter and Paul Cathedral.]]
Among the innovations in the cathedral was the pulpit placed on the left column on the left side of the Royal Doors. The addition of the pulpit, that was installed before the consecration of the cathedral, was noted, contemporarily, as out of the ordinary for an Orthodox church.