The Madrasa of Ilgay El-Yussufi lies in Suq El-Selah Street. The Madrasa was built by Prince Seif El-Din Gay Ibn Abdullah El-Yussufi who was the commander in chief of the armies in the late Bahri Mamluk period and the husband of El-Sultan Shaban's mother. He occupied a very important position in the government for a short period and he was called the sword bearer. After the death of his wife, he conflicted with her son Sultan Shaban and this conflict ended by his death drowning in the Nile. He was buried in that Madrasa. The façade of the Madrasa contains four bays some of them are finely decorated with cornices and others with arches. The Madrasa consists of a huge court surrounded by four naves. The remains of these naves highlight that they were luxuriously decorated. The Minbar of the Madrasa is also half ruined but there are still some handsome decorations that appear on it.
The Minaret of the Madrasa consists of three stories and has a ribbed dome that differs from the common design that was used before. The Madrasa resembles the late Bahri Mamluk style of decoration in using geometrical designs and contrasting shapes such as the vertical thrust of the Minaret and the rectangular frame of the gate. The Sabil was added in the northwest corner of the complex by the end of the Bahri Mamluk period. Its window is covered with Mashrabiya grills. The area above the Sabil was dedicated for the Kuttab which is a place for studying Quran.
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