St. Alexander Nevski Cathedral is the largest church-monument on the Balkan Peninsula. The temple is the central patriarch’s cathedral of the autonomous Bulgarian Orthodox Church and one of the most significant monuments of culture in Sofia. It was built between 1882 and 1912, in honour of the Russian king Alexander II, called "Tsar Osvoboditel" ("King Liberator"), because his army helped liberate Bulgaria from Ottoman rule in 1878. The Church is built to the designs of the Russian architect Pomerantsev in Neo Byzantine style, typical for Russia in the middle of the 20th century. With five aisles and three altar iconostasis (the central altar, dedicated to the Russian saint Alexander Nevski, the southern altar to St. Boris Mihail, who brought Christianity to Bulgaria, and the northern altar to Saints Cyril and Methodius, who created the Cyrillic alphabet), the cavernous interior of the church is full of interesting details made by both Russian and Bulgarian artists.  In the crypt of the cathedral, to the left of the main entrance is located the Icon Museum.