Buq'ah-i Shah 'Ala al-Din Muhammad, known locally as Shahshahan, is a funerary complex located in the vicinity of the Friday Mosque of Isfahan, some distance to the north. Built in phases, the complex consists of a mausoleum dated by inscriptions to 1446-1448/850-852 AH, and a madrasa-Husayniyya dated by its tile mosaic decoration to approximately 1500/905 AH. The complex is named after a martyred descendant of Husayn b. 'Ali b. Abi Talib. The complex saw some additions over its lifespan, and has been altered in recent years since the time of Golombek and Wilber's description, cited below.

The complex is situated on a neighborhood square (maydan), which adjoined the complex on its east side. The mausoleum, which takes the form of a domed cube, protrudes into the square on the east side of the complex, and dominates its visible facade. Fronting the mausoleum structure on its east and south sides facing the maydan is a facade with arched recesses containing shops that open onto the maydan. This feature is a later addition to the mausoleum. Two entrances in the shop facade, one on its south and on on its east side, lead onto corridors that give direct access to the tomb chamber. The tomb chamber is square with entrances on its east and south sides (from the maydan), and on its west side (from the madrasa). The north side has a deep niche. Shallower niches flank this deeper niche, as well as the entrances on the other three sides.

The madrasa portion of the complex lies to the west of the mausoleum, and is arranged around a central rectangular courtyard. A large iwan-portal gives direct access to this portion of the complex from the maydan. This iwan-entrance leads onto a vestibule that in turn gives access to a corridor leading onto the southeast corner of the courtyard. The courtyard is rectangular and has iwans on its two short ends (east and west), and arcades running along its long sides (north and south).

The tiles and painted decorations within the dome chamber appear to be modern. A tile mosaic spandrel on the iwan in the madrasa-Husayniyya is original Timurid work.

Sources:

Golombek, Lisa and Donald Wilber. The Timurid Architecture of Iran and Turan. Princeton: Princeton University Press, 1988. Cat. No. 169A-B (p. 382-4).