The mosque built by Amir Assanbugha ibn Baktamur in 1370 has a facade unique in its articulation with openings whose shapes and scale give the monument a domestic character. A square volume was carved out of the corner of the front facade at the street level to house a sabil, and a round pier surmounted by a muqarnas capital is placed at the corner to sustain the mass of the second story above the sabil with its protruding balcony and mashrabiyya. The sabil is screened off with a mashrabiyya which displays the emblem of the silahdar (armorer).
The constricted site along with the plan's complex geometry, generated by the divergence between the street facade and Mecca orientation and by the accommodation of a typical bent entrance as well as a sabil at the corner, left a small space too irregular for building a square base for a minaret to rise from. The architect responded to this challenge by introducing, for the first time, a triangular base. The octagonal second story was used as a transitional zone between the square base and the round top. In the minaret of Assanbugha the hexagonal second story was the natural choice for such a transition. The interlaced high-relief moldings carved around the circular shaft of the stone minaret of Assanbugha make their first appearance here on a minaret.
Behrens-Abouseif, Doris. The Minarets of Cairo. Cairo: American University in Cairo Press, 1985.