Throughout history, Cairo has witnessed many civilizations and states, sometimes serving as the capital of the Arab Islamic state, and at other times as the capital of non-Arab states, such as the Fatimid and Ottoman states. Cairo is a city of great strategic and economic importance in the Arab world, and is home to many historical, cultural, and archaeological landmarks that attract tourists from all over the world. Among the famous archaeological landmarks in Cairo are the Pyramids and the Egyptian Museum, whose history dates back to the Pharaonic civilization that flourished in Egypt more than five thousand years ago. The Pyramids, located In the Giza plateau on the outskirts of Cairo, are one of the seven wonders of the ancient world, and are considered an architectural and engineering marvel. They were built during the Old Kingdom period of ancient Egypt, and served as tombs for pharaohs and their consorts. The Egyptian Museum, located in Tahrir Square in downtown Cairo, is one of the largest and most important museums in the world, housing over 120,000 artifacts from ancient Egypt, including the treasures of King Tutankhamun.