The enormous central courtyard is a vast square space surrounded by four monumental iwans (vaulted chambers open on one side), of which the qibla iwan (the iwan in the direction of prayer) is larger than the other three. This space acted as a Friday mosque accessible to the public, but it was also used for teaching by the madrasas that were part of the foundation. The four iwans are said to have each been devoted to the teaching of one of the four maddhabs (schools of thought) of Sunni Islamic jurisprudence: the Hanafi, Hanbali, Maliki, and Shafi'i maddhabs. The size of the main qibla iwan was frequently acknowledged as an awe-inspiring achievement, with Mamluk historians like Maqrizi claiming it was greater than the famous arch of the Sassanid Persian palace of Ctesiphon (still the largest single-span vault of brickwork in the world today). The iwan of Sultan Hasan's mosque is not actually as large as that arch, but the comparison nonetheless emphasized the building's legendary reputation. This iwan is also richly decorated. A monumental inscription in Kufic style, set against a swirling vegetal arabesque background, runs along the entire length of the iwan and is unique in Mamluk architecture. The text is a fragment of the Surat al-Fath (Sura of Victory) from the Qur'an. Below this inscription band, the qibla wall is covered in multicolored marble paneling, centered around the mihrab (the niche symbolizing the direction of prayer) which is framed by its own golden inscription and whose central half-dome hood features a sunrise motif radiating from the word "Allah". The stone and marble minbar (pulpit) next to it may have once been covered in inlaid geometric patterns like that on the minbar of the Mosque of Aqsunqur, but this is not visible today. The minbar does still feature finely-crafted bronze doors with geometric patterns. A dado of marble also runs along the other two walls of the iwan, although at a much shorter height. A stone platform, known as a dikkat, stands in the middle of the space and was where reciters of the Qur'an would recite aloud for communal prayers. The other three iwans and the rest of the courtyard are largely plain except for the doorways at the corners of the courtyard. These doorways lead to the madrasa units and with their own smaller courtyards. They are framed in ablaq stonework, bands of stone inscriptions, and colored