The Mosque-Madrasa of Sultan Hassan is a monumental mosque and madrasa located in the historic district of Cairo, Egypt. It was built between 1356 and 1363 during the Bahri Mamluk period, commissioned by Sultan an-Nasir Hasan. It was an impressive architectural achievement for its time. At 150 metres (492 feet) in length, with its tallest minaret towering 68 metres (223 feet) above Cairo's old city, it is one of the largest mosques in the world.