Cairo is the capital of Egypt and the largest city in the Arab world. Its metropolitan area, with a population of over 20 million, is the largest in Africa, the Arab world, and the Middle East, and the 15th-largest in the world. Cairo is associated with ancient Egypt, as the famous Giza pyramid complex and the ancient city of Memphis are located in its geographical area. Located near the Nile Delta, Cairo was founded in 969 AD by the Fatimid dynasty, but the land composing the present-day city was the site of ancient national capitals whose remnants remain visible in parts of Old Cairo. 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 is considered a World City with a "Beta +" classification according to GaWC.