linguistic:paraphrasing
Transformation of conquered towns

More often than founding new cities, the new Islamic rulers took over existing towns. Most of the new Arab settlers nonetheless settled into previously existing urban centers throughout the conquered territories. These cities were transformed according to the needs of the new Islamic society and Islamic facilities were inserted into the existing urban fabric after the conquest. In the case of Damascus and Aleppo, for example, the cities were largely of Roman-Byzantine heritage and their topography changed slowly. The Islamic presence was signaled at first only by the presence of a mosque (and, in Damascus, the royal palace). This transformation, which resulted in what is often regarded as the traditional "Islamic" city, occurred over a long period and was shaped by multiple social and economic causes that varied according to region and period. The arrival of Islamic rule was only one stage in a process that had already begun by the 6th century.

The principle of arranging buildings is known as "horizontal spread". Residencies and public buildings as well as private housing tend to be laid out separately, and are not directly related to each other architectonically. Archaeological excavations at the city of Jerash, the Gerasa of Antiquity, have revealed how the Umayyads have transformed the city plan.