sentences:  The city has a number of Byzantine monuments, as well as post-Byzantine churches built on Byzantine foundations.The most significant Byzantine monument is the Anastasis Church (Church of the Resurrection) with its "spectacular frescoes" from 1315, bearing comparison with some of the finest works of Palaiologan art in the main Byzantine centres of Thessaloniki and Constantinople.Of the city's thirteen mosques, eight survive, including the Old Metropolis, which had been converted into the Hünkar Mosque, as well as the Orta Mosque, Mendrese Mosque, and the Mahmud Çelebi Mosque.