The Rotunda (also known as the Church of Agios Georgios or (in English) the Rotunda of St. George) - Thessaloniki, Greece. The building was used as a church for over 1,200 years until the city fell to the Ottomans. In 1590 it was converted into a mosque, called the Mosque of Suleyman Hortaji Effendi (as depicted on this postcard), and a minaret was added to the structure. It was used as a mosque until 1912, when the Greeks captured the city during the Balkan War.