The St. George's (Yuriev) Monastery is usually cited as Russia's oldest monastery. It was used to be the most important in the medieval Novgorod Republic. It is part of the UNESCO World Heritage Site named Historic Monuments of Novgorod and Surroundings.
According to legend, the monastery was founded in the 11th century by Yaroslav the Wise (whose Christian name was George), but the first historically-reliable reference to it is from the early 12th century when the main church the Church of St. George (Georgieveskii Church) was founded (in 1119) by Prince Vsevolod Mstislavich of Novgorod and Pskov and Hegumen (roughly equivalent to a western prior) Kyuriak (Kirik) and built by the master Peter.
By the first third of the 13th century the hegumen had been raised to the status of an archimandrite (roughly equivalent to an abbot, i.e., the head of an important monastery, although the comparison with western abbots is imprecise).
The monastery was an important source for historical information on medieval Novgorod, as part of the Novgorod First Chronicle (the Synodal text) was compiled in the monastery.
The Church of St. George is one of the largest in Novgorod and its immediate environs. It is a tall white-stone church with three silver domes, which is unusual for Russian churches which usually have five domes (the main dome representing Christ, the four smaller ones representing the evangelists). Some remnants of the medieval frescoes remain, but most of the church was repainted in 1902. Among the frescoes is a large Christ Pantokrator in the main dome, a full-length portrait of Novgorodian Archbishop Feoktist, and another full-length (although smaller) portrait of Prince Vsevolod Mstislavich on the southwestern pier.
The monastery also has the Church of the Exaltation of the Cross in the northeastern corner of the monastery, with five blue domes and gold stars on it, built in the 18th century. The gateway into the monastery is crowned by a tall gold-domed tower which is visible from the city centre, including the Novgorod Kremlin two miles to the north.
The monastery was ravaged during the Soviet rule. Five of its six churches were destroyed by 1928; the monastery was closed in 1929. During the World War II, the buildings were occupied by the German and Spanish armed forces, and were seriously damaged. In 1991 the monastery was returned to the Russian Orthodox Church, and parts of it have been renovated since then. However the western part, including a church there, are still in ruins.References:
The Petersberg Citadel is one of the largest extant early-modern citadels in Europe and covers the whole north-western part of the Erfurt city centre. It was built after 1665 on Petersberg hill and was in military use until 1963. It dates from a time when Erfurt was ruled by the Electors of Mainz and is a unique example of the European style of fortress construction. Beneath the citadel is an underground maze of passageways that can be visited on guided tours organised by Erfurt Tourist Office.
The citadel was originally built on the site of a medieval Benedictine Monastery and the earliest parts of the complex date from the 12th century. Erfurt has also been ruled by Sweden, Prussia, Napoleon, the German Empire, the Nazis, and post-World War II Soviet occupying forces, and it was part of the German Democratic Republic (East Germany). All of these regimes used Petersberg Citadel and had an influence on its development. The baroque fortress was in military use until 1963. Since German reunification in 1990, the citadel has undergone significant restoration and it is now open to the public as a historic site.