Cairo ( KY-roh; Arabic: القاهرة, romanized: al-Qāhirah, Egyptian Arabic pronunciation: [el.qɑ(ː)ˈheɾɑ] ) is the capital of Egypt and the Cairo Governorate, and is the country's largest city, 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 the 12th-largest in the world by population with over 22.1 million people.

Cairo is associated with ancient Egypt, as the Giza pyramid complex and the ancient cities of Memphis and Heliopolis are located in its geographical area. Located near the Nile Delta, the city first developed as Fustat following the Muslim conquest of Egypt in 641 next to an existing ancient Roman fortress, Babylon. 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 It later superseded Fustat as the main urban centre during the Ayyubid and Mamluk periods (12th–16th centuries).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 long been a centre of the region's 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.