The Hagia Sophia Museum was originally an Eastern Orthodox cathedral in the Byzantine Empire. Its construction began in 537 AD at the beginning of the Middle Ages and then converted into a mosque during occupation by the Ottoman Empire. It has now been secularized and converted into Turkey’s most visited museum, with preserved murals covering the plaster walls. Most have been restored to resemble their original appearance. The building is a true spectacle featuring the overlap of Christianity and Islam, and is a very special site well worth visiting.