The Sultan Hassan Mosque is considered stylistically the most compact and unified of all Cairo monuments. It is one of the masterpieces of Mamluk architecture. The building was commissioned by Sultan Hassan bin Al-Nasir Muhammad bin Qalawun in 1356 AD as a mosque and religious school for all four juristic branches of Sunni Islam. It was designed so that each of the four schools of thought - Shafi, Maliki, Hanafi and Hanbali - has its own area while sharing the mosque.[1].

Source. en.wikipedia.org/wiki/Mosque-Madrassa_of_Sultan_Hassan

The Al-Rifa'i Mosque (Arabic: مسجد الرفاعى‎, transliterated also as Al-Rifai, Al-Refai, Al-Refa'i, and named in English the Royal Mosque), is located in Cairo, Egypt, in Midan al-Qal'a, adjacent to the Cairo Citadel. The building is located opposite the Madrassa of Sultan Hassan, which dates from around 1361, and was architecturally conceived as a complement to the older structure. This was part of a vast campaign by the 19th century rulers of Egypt to both associate themselves with the perceived glory of earlier periods in Egypt's Islamic history and modernize the city. The mosque was constructed next to two large public squares and off of several European style boulevards constructed around the same time.

Source . en.wikipedia.org/wiki/Al-Rifa'i_Mosque More .. archnet.org/library/sites/one-site.jsp?site_id=3476

The Saladin Citadel of Cairo (Arabic: قلعة صلاح الدين‎ Qalaʿat Salāḥ ad-Dīn) is a fortification in Cairo, Egypt.

The location, part of the Muqattam hill near the center of Cairo, was once famous for its fresh breeze and grand views of the city, and was fortified by the Ayyubid ruler Salah al-Din (Saladin) between 1176 and 1183 AD, to protect it from the Crusaders[1].