Hagia Sophia (lit. 'Holy Wisdom'; Ancient Greek: Ἁγία Σοφία (Hagía Sophía), Turkish: Ayasofya), is a mosque and major cultural and historical site in Istanbul, Turkey. It was erected three times by the Eastern Roman Empire. The present Hagia Sophia is the third, built in 537 AD. It carried several titles over its long history, serving as an Orthodox church (with a brief period as a Catholic cathedral due to the Fourth Crusade), a mosque, a museum, and then a mosque again. Though Byzantine-made, it has long since received Islamic additions, such as its famous minarets.
