Islamic Cairo (Arabic: قاهرة المعز‎, meaning: Al-Mu'izz's Cairo), also called Historic Cairo or Medieval Cairo, refers generically to the historic areas of Cairo, Egypt, that existed before the city's modern expansion during the 19th and 20th centuries; particularly the central parts around the old walled city and around the Citadel of Cairo. The name "Islamic" Cairo refers not to a greater prominence of Muslims in the area but rather to the city's rich history and heritage since its foundation in the early period of Islam, while distinguishing it from with the nearby Ancient Egyptian sites of Giza and Memphis. This area holds one of the largest and densest concentrations of historic architecture in the Islamic world. It is characterized by hundreds of mosques, tombs, madrasas, mansions, c