Walls_of_Palmyra
The walls of Palmyra are a series of protective fortifications that providing customs barrier as well as protection for Palmyra from invaders and Bedouins. The development process of the walls can be separated into three stages; the first dates to the first century AD, and the second dates to the reign of the Roman Emperor Aurelian in the third century. The third was an improvement of the Aurelian walls commissioned by emperor Diocletian in the fourth century. The pre-Aurelian walls did not encircle the whole city and were not designed to protect it from conquest, but to provide protection from marauders. The Aurelian and Diocletian walls, although surrounding a smaller area, provided a higher degree of protection as they tightly enclosed the city.