Topkapi Palace is one of the most important historical buildings in Istanbul. It was the primary residence of the Ottoman Sultans for 400 years (1465-1856) and served as the center of the Ottoman Empire during that time. The palace complex consists of four main courtyards and many smaller buildings. The First Court was the official and public entrance to the palace, and it was here that the Sultan held his audiences. The Second Court was the private domain of the Sultan and his family, and it was here that they lived and worked. The Third Court was the home of the palace’s service staff and the Fourth Court was the site of the imperial treasury and the harem. The harem was the private residence of the Sultan’s wives, children, and concubines, and it was off-limits to everyone else. The harem was a self-contained world within the palace, and it had its own schools, mosques, and baths. The harem was guarded by the Sultan’s eunuchs, who were castrated men who served as the Sultan’s personal bodyguards. The Topkapi Palace was a symbol of the power and wealth of the Ottoman Empire, and it was one of the most magnificent palaces in the world. Today, the Topkapi Palace is a museum, and it is one of the most popular tourist attractions in Istanbul.