Cairo ( KY-roh; Arabic: القاهرة, romanized: al-Qāhirah, Egyptian Arabic: [el‿ˈqɑːheɾɑ] ) is the capital and largest city of Egypt and the Cairo Governorate, being home to more than 10 million people. It is also part of the largest urban agglomeration in Africa, the Arab world, and the Middle East. The Greater Cairo metropolitan area is one of the largest in the world by population with over 22.2 million people.

The area that would become Cairo was part of ancient Egypt, as the Giza pyramid complex and the ancient cities of Memphis and Heliopolis are near-by. Located near the Nile Delta, the predecessor settlement was Fustat following the Muslim conquest of Egypt in 641 next to an existing ancient Roman fortress, Babylon. Subsequently, Cairo was founded by the Fatimid dynasty in 969. It later superseded Fustat as the main urban centre during the Ayyubid and Mamluk periods (12th–16th centuries).

Cairo has since become a longstanding centre of political and cultural life, and is titled "the city of a thousand minarets" for its preponderance of Islamic architecture. Cairo's historic center was awarded World Heritage Site status in 1979. Cairo is considered a World City with a "Beta +" classification according to GaWC.

Cairo has the oldest and largest film and music industry in the Arab world, as well as Egypt's oldest institution of higher learning, Al-Azhar University. Many international media, businesses, and organizations have regional headquarters in the city; the Arab League has had its headquarters in Cairo for most of its existence.

Cairo, like many other megacities, suffers from high levels of pollution and traffic. The Cairo Metro, opened in 1987, is the oldest metro system in Africa, and ranks amongst the fifteen busiest in the world, with over 1 billion annual passenger rides. The economy of Cairo was ranked first in the Middle East in 2005, and 43rd globally on Foreign Policy's 2010 Global Cities Index.