from Wikipedia Cairo:
Cairo (Arabic: القاهرة transliteration: Al-Qāhirah), which means "The Vanquisher" or "The Triumphant", is the capital city of Egypt. It is the largest city in Egypt and Africa's most populous city. While Al-Qahirah is the official name of the city, in Egyptian Arabic it commonly shares the dialect's name for the country, transliteration: Masr. Inhabitants of Cairo are called Masraweya rather than Masri within Egypt.
Cairo was founded by the Fatimid caliphs as a royal enclosure, and replaced Fustat as the seat of the government. It later came under the Mamluks, ruled by the Ottomans 1517 to 1798, briefly occupied by Napoleon. Muhammad Ali of Egypt made Cairo the capital of his independent empire from 1805 to 1882, after which the British took control of it until Egypt attained independence in 1922.
Cairo has a population of about 7.7 million people, while its metropolitan area has a population of about 17.285 million people. Cairo is the sixteenth most populous metropolitan area in the world. It is also the most populous metropolitan area in Africa.
Today, Greater Cairo encompasses various historic towns and modern districts into one of the most populous cities in the world. A journey through Cairo is a virtual time travel: from the Pyramids, Saladin's Citadel, the Virgin Mary's Tree, the Sphinx, and Heliopolis, to Al-Azhar, the Mosque of Amr ibn al-A'as, Saqqara, the Hanging Church, and the Cairo Tower. It is the Capital of Egypt, and indeed its history is intertwined with that of the country. Today, Cairo's official name is Al-Qahira (Cairo), although the name informally used by most Egyptians is "Masr" (Egyptian Arabic name for Egypt), from the original name of Egypt's first Arab capital Fustat, Misr al-Fustat, "City of the Tents."