The Masjid-i Shah Vali is located in the township of Taft, situated approximately twenty-six kilometers southwest of Yazd. It has been deduced from historical writings that Khanish Begum, sister of Shah Tahmasp (1524-1576) and wife of Nu'aym al-Din Ni'matullah Baqi, was responsible for the building of the Masjid-i Shah Vali between 1468 and 1484.
The Masjid-i Shah Vali is composed of a large square domed central hall flanked by long rectangular halls to the east and west. The hall to the west is a later construction believed to have replaced the original hall, probably a mirror copy of the one to the east. The main chamber of the mosque is entered from the northeast via an iwan and a long hall, which do not follow the main northeast-southwest axis of the mosque. The original entrance of the masjid is believed to have been the back wall of the long iwan hall preceding the dome chamber. Here, set within a frame of mosaic faience dated to 1484, are latticed wooden doors, above which is a triangular "pediment" of carved wood.
On its exterior, the Masjid-i Shah Vali is surrounded on all sides by the urban fabric of Taft, and therefore its individual elevations cannot be described. An entrance alcove follows the long entrance hall and precedes the main chamber. Each wall of the main square chamber hall is similarly organized in a tripartite arrangement, with a larger bay at the center flanked by a doorway on either side, adjacent to the corner. Opposite the entrance alcove is the qibla wall, where the central bay is articulated as a semi-octagon with the mihrab recess set in its central facet. The large central bays on the opposite sides lead into the rectangular prayer halls to the east and west.
The dome measures 10.5 meters across and is supported by eight massive piers and arches framing each of the bays and the four corner piers. Instead of corner squinches, the corners are open galleries with arches connecting two of the lateral piers. The corner pier is connected to this arch with a quarter dome that serves to buttress the lateral piers. Pendentives span between each of the lateral and corner arches to the springing of the dome.
The original prayer hall to the east of the main chamber is flanked by a smaller rectangular hall on either side, followed by two more halls (of narrower but longer dimensions) to the northeast side. The prayer hall to the west is presumably articulated in a similar fashion. The doorways at the corners of the lateral walls of the main domed chamber lead into the smaller rectangular prayer halls to the east and west. Along the qibla wall these lead to small rooms, while on the northeast entrance side these lead to staircases that give access to upper-story galleries. At present only the staircase to the east is in use. The upper-story galleries are organized as on the ground floor, with openings between the pointed arches connecting the piers.
The main dome chamber has whitewashed walls and is decorated only with a perimeter dado of hexagonal blue tiles framed with a strip of mosaic faience. The rest of the mosque is decorated simply with plaster, carved and molded following the lines of the architecture. The bays surrounding the main domed chamber each have stellate vaults. Located in the mihrab niche is a marble stone slab measuring 125 by 64 centimeters that is decorated with a candle pattern and floral engravings.
Sources: http://archnet.org/library/sites/one-si ... e_id=15165