Most of the buildings in the Bayn al-Qasrayn area were built on top of the foundations or ruins of the palaces. One of the main courtyards in the maristan (hospital) of Sultan al-Mansur Qalawun (built in 1285) incorporates remnants of the Western Fatimid Palace, in particular some carved stucco windows in its eastern iwan, probably part of what was originally a palace courtyard which had four iwans arranged in a cross formation.[1][2]: 58 Likewise, the lobed fountain in the middle of the courtyard of Qalawun's madrasa (in the same complex) also belonged to that palace.[8] The 13th-century Madrasa of al-Salih Ayyub was built in part over the former kitchens of the palace.[8] The Khanqah of Sultan Baybars al-Jashnakir (built in 1306-1310) and the Madrasa of Amir Qarasunqur (built in 1300) stand on the site of the former residence of the Fatimid viziers, which faced a western gate of the Eastern Palace.[3] The large iron window grille in the exterior facade of the mausoleum of Baybars al-Jashnakir's khanqah was originally an artifact brought from the Abbasid palaces in Baghdad and used in the Fatimid viziers' palace.[8] The old Ayyubid minaret at the entrance of the al-Hussein Mosque is built over one of the Fatimid Eastern Palace's former gates (cited as the "Bab al-Akhdar" but perhaps the same as the Bab al-Daylam) as the shrine of al-Hussein was originally adjoined to the palace.[8]