What should you know before visiting Hagia Sophia?
Built in 537 CE by Byzantine Emperor Justinian I, Hagia Sophia (Ayasofya) was the world's largest cathedral for 1,000 years. Converted to a mosque in 1453 after Ottoman conquest, then a museum (1935-2020), it's now a functioning mosque again. This UNESCO World Heritage Site showcases breathtaking Byzantine architecture, stunning mosaics, and Islamic calligraphy in one extraordinary space.