Khan al-Mirjan is situated in Baghdad's eastern neighborhood, Al Rusafah, at the end of Suq al Thulatha' known today as the drapers' suq or Suq al-Bazzazin. It was built in 1358 by the Wali Amin al-Din Mirjan and belongs to the waqf of the madrasa Mirjaniyyah built by the same wali as explained in the inscription above the entrance. The materials used were brick and wood.
The building is rectangular in plan 31.5 by 45 meters, occupying two floors. It has two entrances one from the suq al-Thulatha' and the second from Dar al Khilafa today known al Samu'al Street. It is accessible from Suq al Thulatha' on its ground floor through a pointed arch. The spandrel of the arched doorway is filled with minute arabesque scrolls and bordered with a decorative band containing different types of interlaced scrolls. Above this are nine lines of calligraphic inscriptions according to the Nashki design. The khan penetrates the street on its northern side where it juts beyond the building's main mass. The entrance hall measures 2.5 by 3 meters from which two staircases of 1.5 meters wide provide access to the second floor.
The entrance leads to the main hall spanning 10.8 by 29.5 meters, with a fountain at its middle. Twenty-two rooms of different size are located on the ground floor and open through a pointed arched door onto the central hall. Corner rooms are larger than the others to accommodate the corner situation. Their access is chamfered at forty-five-degrees between the sides of the main hall. Middle rooms on every side of the hall have a lobed arch framing their opening. Dormer-windows rest on top of every room door.
The second entrance from Samu'al Street lies in the southern side of the Khan, facing Suq-Thulatha's entrance hall. The access door is 3.5 meters wide leads to a large iwan measuring 3.4 by 6.2 meters that is flanked by three rooms on each side and opens to the main hall.
The second floor, measuring six meters from the ground floor, includes a one-meter wide, open air corridor (riwaq) serving the twenty-five rooms overlooking the main hall. The passage is held by supports decorated with muqarnas on the upper two sides of every door of the lower level. The second floor layout is identical to the ground floor except for the entrance spanning the height of the two floors and the additional three rooms over the iwan on the southern side.
The main hall differs from other khan's courtyard as it is covered (in Turkish it is called Khan Ortumah, meaning covered khan). The roof is elevated 14 meters from the ground floor. It is composed of eight transverse pointed arches each are two meters wide and placed at equal intervals except the middle bay that is larger (approximately three meters). They span the shortest side, from north to south. Between each of the double arches, the vault goes in steps culminating in a dome on squinches. Windows within these spaces admit light to the central hall. This roofing and lighting feature is unique in Islamic architecture. According to the waqfiya, the building was used as a market place and an inn with shops on the ground floor and rooms on the upper floor. People from Khurassan know the market as Khan al-Yatim or the merchant's khan. Its covered courtyard was used to accommodate animal and load merchandise.
Sources:
Michell, George, Ed: 1978. Architecture of the Islamic World. London, Thames and Hudson, 248.
Strika V. and Khalil J. 1987. The Islamic Architecture of Baghdad. Naploli: Instituto Universitario Orientale, 75-78.
Uluçam, Abdüsselam. 1989. Irak'taki Türk Mimari Eserleri. Ankara: Kültür Bakanligi, 166-169.