Bab al-Maqam, built by al-Aziz Muhammad in 1230 on the road that connected the Maqamat with the Citadel. It is unique in its planning and form. The design's innovative quality implies a monumental, ceremonial function rather than a military one.
Yasser Tabbaa presents an argument that supports this hypotheses. He explains how this gate differs from nearly all other medieval Syrian gates in three very important respects: it has no defense towers; it has a straight instead of a bent axis; and it has three openings instead of one. Most of the gates built after this one were developed for defense reasons; one opening to control access, bent axes to prevent direct passage and two massive defense towers. Bab al- Maqam is the only tripartite gate built in the Ayyubid period. Though triumphal arches are a rare Islamic architecture type, Tabbaa points to the existence of several precedents such as Bab al-Maydan in Fustat, a brick arch at the foothill of Qal'at-i al Bust and the Gate of Wine at the Alhambra palace. These precedents reinforce the possibility of Bab al-Maqam's ceremonial program both religious, a point of entry to pay homage to Abraham, and political, countering the Shi'i shrines (Mashhad al-Dikka and Mashhad al-Husayn) to the east.
Source:
Tabbaa, Yasser, 1997, Constructions of Power and Piety in Medieval Aleppo, The Pennsylvania State University Press, pp. 67-69.