Hagia Sophia, the Church of Holy Wisdom, is an ancient cathedral of the Church of Constantinople located in modern-day Istanbul. It was converted to a mosque by the Turks and is now used as a museum. It is universally acknowledged as one of the great buildings of the world and a reference point in history of architecture. The basilica of Hagia Sophia, the one that you can visit today, was build in the 6th century, under the direction of the Byzantine emperor Justinian I. The building combines a longitudinal basilica and a centralized building in a wholly original manner, with a huge 32-metre main dome supported on pendentives and two semidomes. In 1934 Hagia Sofia was secularized and converted into a museum so everybody could come to visit this architectural masterpiece and admire both Christian and Muslim art.