The city is known for the variety and age of its medieval monuments. The foremost among these is the St. Sophia Cathedral, built between 1045 and 1050 under the patronage of Vladimir Yaroslavich, the son of Yaroslav the Wise; Vladimir and his mother, Anna Porphyrogenita, are buried in the cathedral. It is one of the best preserved churches from the 11th century. It is also probably the oldest structure still in use in Russia and the first one to represent original features of Russian architecture (austere stone walls, five helmet-like domes). Its frescoes were painted in the 12th century originally on the orders of Bishop Nikita (died 1108) (the "porches" or side chapels were painted in 1144 under Archbishop Nifont) and renovated several times over the centuries, most recently in the nineteenth century. The cathedral features famous bronze gates, which now hang in the west entrance, allegedly made in Magdeburg in 1156 (other sources see them originating from Płock in Poland) and reportedly snatched by Novgorodians from the Swedish town of Sigtuna in 1187. More recent scholarship has determined that the gates were most likely purchased in the mid-15th century, apparently at the behest of Archbishop Euthymius II (1429–1458), a lover of Western art and architectural styles. The Novgorod Kremlin, traditionally known as the Detinets, also contains the oldest palace in Russia (the so-called Chamber of the Facets, 1433), which served as the main meeting hall of the archbishops; the oldest Russian bell tower (mid-15th century), and the oldest Russian clock tower (1673). The Palace of Facets, the bell tower, and the clock tower were originally built on the orders of Archbishop Euphimius II, although the clock tower collapsed in the 17th century and had to be rebuilt and much of the palace of Euphimius II is no longer standing. Among later structures, the most remarkable are a royal palace (1771) and a bronze monument to the Millennium of Russia, representing the most important figures from the country's history (unveiled in 1862). Outside the Kremlin walls, there are three large churches constructed during the reign of Mstislav the Great. St. Nicholas Cathedral (1113–1123), containing frescoes of Mstislav's family, graces Yaroslav's Court (formerly the chief square of Novgorod). The Yuriev Monastery (one of the oldest in Russia, 1030) contains a tall, three-domed cathedral from 1119 (built by Mstislav's son, Vsevolod, and Kyurik, the head of the monastery). A similar three-domed cathedral