The Church of the Holy Wisdom, also known as Hagia Sophia, is a historic architectural marvel located in Istanbul, Turkey. Originally constructed as a cathedral in 537 AD during the reign of Emperor Justinian I, it served as the center of the Eastern Orthodox Church for nearly a thousand years. Its massive dome and intricate mosaics showcase the artistic and engineering achievements of the Byzantine Empire. In 1453, after the conquest of Constantinople by the Ottoman Empire, the church was converted into a mosque. In 1935, it was secularized and turned into a museum, attracting millions of visitors. In 2020, it was reconverted into a mosque, while still remaining open to visitors.