The grain provisioning of the Ottoman capital city Istanbul for the subsistence of its considerable population, including the court, the military, and the religious institutions, was maintained through the same location on an extramural landing square along the wharfs of the Golden Horn from the mid-fifteenth century up until the mid-nineteenth century: the Unkapanı. This article addresses the urban architecture of Istanbul Unkapanı as an illustration of the Ottoman official distribution centers referred to after public weighing scales as kapan. Here, the buildings constituting the Unkapanı—the great magazine as the hall of the public weighing scale for grain, the mosque, and the tradesmen council house (dîvânhâne or cardak)—are identified and represented on the evidence of the original textual and visual sources, while the urban patterns through the landing square from the wharfs to the city gate are mapped.