Step into the heart of Istanbul's fascinating history with a professional, official guide on this 5-hour tour of Topkapı Palace and Hagia Sophia. Enjoy skip-the-line access to bypass the long ticket queues, especially helpful during the busy high season from April to the Christmas period. At Topkapı Palace, explore the lavish Harem, the sacred relics of the Ottoman Empire, and historic Hagia Irini, the city's oldest Byzantine church. Then visit Hagia Sophia, the 1,500-year-old cathedral famed for its soaring dome and intricate mosaics, for a memorable journey through Istanbul's past.