The Mosque-Madrasa of Sultan Hasan (Arabic: مسجد ومدرسة السلطان حسن) is a monumental mosque and madrasa located in Salah al-Din Square in the historic district of Cairo, Egypt.

[3] The mosque's construction is considered all the more remarkable as it coincided with the devastation wrought by the Black Plague, which struck Cairo repeatedly from the mid-14th century onwards.

[1] The amir's high standing otherwise was another indication of this prestige, as he was appointed governor of Cairo in 1330 and oversaw other construction projects including the renovation of the hippodrome established by al-Zahir Baybars near the Citadel.

The most substantial available source concerning the mosque's construction is al-Maqrizi, writing six decades afterwards, as he had access to administrative documents that are unavailable to historians today.

[1] The importance and scale of the building project also attracted craftsmen from all over the Mamluk empire, including the far-away provinces of Anatolia, which may explain the diversity and innovativeness of the mosque's design and decoration.

Al-Maqrizi, noted that "as soon as there occurred strife between the people the state, a number of amirs and others ascended to the top of the mosque and began to bombard the Citadel from there".

[2] Even in the 18th century, during the period of Ottoman control, the mosque was apparently closed for many years after unrest in 1736, and was only reopened in 1786 by order of Salim Agha.

[1] It stands on the site of a lavish palace which had previously been built at great cost by Hasan's father, Sultan al-Nasir Muhammad, for one of his amirs, Yalbugha al-Yahawi, and which was demolished to make way for the mosque.

The square and the former hippodrome nearby (on the southwestern side of the Citadel) were historically used for military parades, equestrian games, and official ceremonies, thus giving the location added symbolic significance.

The building's southwestern and northeastern facades (its longer sides) are marked by vertical rows of eight windows each (spread across four stories inside) which are a unique feature that helps to visually emphasize the structure's height.

[1][2] The top edge of the exterior facades are crowned by a thick cornice of muqarnas (stalactite-like carving) projecting 1.5 meters over the rest of the wall, another unprecedented feature in Mamluk architecture, although it does not extend around the entire building.

The southern one of this pair, which is still in its original form, is the highest minaret of Mamluk architecture, its summit being 84 meters above the street level at the time.

[1] On the inside of the portal, behind the stone benches and flanking the doorway, are a pair of marble niches filled with geometric patterns reminiscent of Qur'an illumination and culminating in shallow muqarnas hoods (also Anatolian in style).

Above these are black marble panels inlaid with white Kufic Arabic inscriptions of parts of the Surat al-Fath (Sura of Victory) from the Qur'an.

[1] The Shahada (the Muslim declaration of faith) is inscribed in "square" Kufic higher up above this, while further up is a band of inscription containing another Quranic verse (24:36-37), running along the full width of the inside of the portal, just below the muqarnas canopy.

Another minor but curious feature is the sculpted image of other architectural buildings in some of the carvings just above the stairs leading up to the portal; these are possibly spoils from a Gothic-style Christian monument, presumably from Crusader churches located on the estates donated to the madrasa-mosque's foundation.

[1] The original bronze-covered doors of the entrance were forcibly purchased at a modest price by Sultan Mu'ayyad in the early 15th century for use on his own mosque, and can still be seen there today.

[2] Although the exterior walls of the building are in stone, much of the interior is brick, with facades covered in stucco and finished with stonework for decorative details.

[2] The vestibule chamber upon entering the mosque is an unusually ornate space, covered by a small central dome surrounded by elaborate muqarnas vaults.

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).

[5] 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.

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.

[3] Additionally, a marked-out but empty band running along the top edge of the entire courtyard, above the iwans, may have been intended for another monumental inscription.

[1] The doors in the corners of the main courtyard each lead to one of the four madrasa devoted to one of the four maddhabs (schools of thought in Sunni Islamic jurisprudence).

This window is distinguished by a set of doors which are notable for their exceptionally fine craftsmanship, made from copper-niello, inlaid with gold and silver, and featuring geometric star patterns and Thuluth-style Arabic inscriptions.

The square chamber transitions gradually to the round dome (12 meters in diameter) with the use of wooden pendentives, typical of Mamluk architecture, which are sculpted into muqarnas forms and richly painted and gilded.

An Italian traveler in the early 17th century described it as being shaped like an egg; more specifically, it started narrow at the bottom then swelled out like a bulb, before finishing in a pointed tip.

[2] The mausoleum is also furnished with a large wooden lectern decorated with geometric star patterns and inlaid with ivory, which was meant to hold one of the giant royal copies of the Qur'an owned by the foundation.