city, Moscow oblast (province), western Russia, northeast of Moscow city. The city developed around the fortified walls of the Trinity-St. Sergius monastery, which was founded there in 1337-40 by St. Sergius of Radonezh. A theological seminary founded in 1742 remains the principal seminary of Russia. The monastic buildings, much visited by tourists, include the Trinity Cathedral (1422-23), containing the tomb of St. Sergius and icons attributed by some scholars to the medieval artist Andrey Rublyov; the Church of the Holy Spirit (1476-77), with its later tower; the Cathedral of the Assumption (1559-85), containing frescoes of 1684; the late 17th-century refectory; and the 18th-century bell tower. There is a museum of toys in the monastery. Modern Sergiyev Posad has engineering and diverse light industries. The city still holds an annual international fair. Pop. (2002) 113,581; (2006 est.) 112,700.
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