The Bibi Khanym Mosque, in central Samarkand, is the largest of its kind in central Asia, it was easily the tallest building in Samarkand until the late 20th century. Intended as the congregational (Friday) mosque of Timur’s beloved Samarkand, it never truly fulfilled its promise as it was beset from the beginning by structural flaws that became apparent almost as soon as it was constructed. Although dubbed the Bibi Khanym mosque following Timur’s chief consort, Saray Mulk Khanum, who is buried nearby, its relationship to Timur’s wife remains uncertain. The Spanish ambassador Clavijo, who visited Samarkand from 1404-06, describes it as being built “in honour of the mother of his [Timur’s] wife Cano [Bibi Khanym]” Nushin Arbabzadah asserts that Bibi Khanum herself endowed both the mosque and the neighboring madrassa which no longer survives, similar to Gawhar Shad’s sponsorship of mosques, madrassas, and other religious institutions a generation later. Blair contends that the mosque was commissioned by Timur but does not indicate for whom it was built.

In spite of its size,  the design of the Bibi Khanum was not especially innovative. Since the 12th century the four-iwan plan mosque had predominated in Persian lands, and Timur’s captive Persian artisans (relocated to Samarkand following the conquest of their homeland) would have been readily familiar with the design, which Bloom describes as a copy of the (now destroyed) mosque of the Ilkhanid sultan Uljaytu at Sultaniyya, Iran. One minor innovation was the addition of domes to the side iwans, turning each into freestanding structures. These side chambers are emblematic of the versatility of Timurid architecture: if viewed in isolation, each are identical to freestanding mausolea, showcasing that for the Timurids, function is not determined by form. The Uzbek conservationists successfully stabilized and restored the collapsing main dome, rebuilt the entrance arch broken in the 1897 earthquake, reconstructed the vanished domes on the side iwans, and everywhere replaced crumbling brick with new masonry indistinguishable from the old.

However, not everyone was pleased with their work. The architectural historian Robert Hillenbrand notes that in the rush to completion certain liberties were taken, such as replacing missing tiles with fanciful interpretations of what may have existed on nearby tiles—a problem resulted in gibberish when used to restore calligraphic bands. He also faulted the construction of a wall around the mosque that is much taller than the original wall, faced on its exterior by a pastiche of Timuresque brickwork that lacks historical accuracy.