The Sopoćani monastery (Serbian Cyrillic: Сопоћани), an endowment of King Stefan Uroš I of Serbia, was built in the second half of the 13th century, near the source of the Raška River in the region of Ras, the centre of the Serbian medieval state. It is a designated World Heritage Site, added in 1979 with Stari Ras. The church was dedicated to the Holy Trinity and completed around 1265, with interior decorated shortly thereafter. Archbishop Sava II, who became the head of the Serbian Orthodox Church in 1263, is represented in the procession of archbishops in the area of the altar. The frescoes of Sopoćani are considered by some experts on Serbian medieval art as the most beautiful of that period. On the western wall of the nave is a famous fresco of the Dormition of the Virgin. In the 16th century the monks had to temporarily leave the monastery on several occasions due to the Ottoman threat. Finally, during one of the raids in 1689 the Ottoman Turks set fire to the monastery and carried off the lead from the church roof. The brotherhood escaped with some important relics to Kosovo - but did not return to Sopoćani; it remained deserted for over two hundred years, until the 20th century. The church slowly decayed: its vaults caved in, its dome fell down, and the remains of the surrounding buildings were covered with rubble and earth.