Kirillo-Belozersky Monastery, properly translated in English as The Assumption monastery of St Cyril, has always rivalled the Solovetsky Monastery as the strongest fortress and the richest landowner of the Russian North.
The monastery was founded in 1397 on the bank of the Siverskoe Lake, to the south from the town of Beloozero, in the present-day Vologda region. Its founder, Saint Kirill of Beloozero , following the advice of his teacher, Saint Sergius of Radonezh, first dug a cave here, then built a wooden Assumption chapel and a loghouse for other monks.
Being a member of the influential Velyaminov clan of boyars, Kirill relinquished the office of father superior of the greatest cloister in medieval Moscow - the Simonov monastery. His ties with the ruling elite were still close, however, as his letters to sons of Dmitri Donskoi clearly demonstrate. It seems that the Muscovite rulers regarded Kirill's monastery as an important strategic point, both for Northern trade and in their struggle with the Novgorod Republic.
In the 16th century, the monastery was the second richest landowner in Russia, after Troitse-Sergiyeva Lavra. Ivan the Terrible not only had his own cell in the cloister, but also planned to take monastic vows here. During the political struggles, the monastery sided with nestiazhateli, who disapproved of church landlordism. The leader of the movement, Nil Sorsky , founded a separate monastery nearby. The cloister was also important as a political prison. Among the Muscovite politicians exiled here were Vassian Patrikeyev, Tsar Simeon Bekbulatovich, Patriarch Nikon, and the great boyar Boris Morozov.
The vast area of the monastery contains buildings from the 15th, 16th, and 17th centuries. The Assumption cathedral, built by Rostov masters in 1497, features many old and precious icons. A lot of valuable objects kept in the cathedral treasury are personal gifts of the tsars who visited the monastery. There are 10 other churches within the cloister, most of them dating from the 16th century. The monastery walls, 732-meter long and 7-meter thick, were constructed in 1654-80. They incorporate parts of the earlier citadel, which helped to withstand the Polish siege in 1612. The walls feature numerous towers, each built to a particular design. The most remarkable are the Chasuble, the Tent-like, the Vologda, and the Smithy towers.
By the 20th century, the town of Kirillov had grown nearby. After the Bolsheviks had the monastery turned into museum (1924), the library and some other treasures were transferred to Moscow or St Petersburg. These included the oldest extant copies of the 12th-century Daniel's Pilgrimage and the Zadonshchina. The monks were readmitted into the monastery in 1998.