The Latin inscription above the main gate of this unusually well preserved Roman fort records that it was built in AD 293-305 by Aurelius Asclepiads, then governor of the province of Arabia, and dedicated to the co Emperors Diocletian and Maximian, sour best and greatest rulers’, and to their two Caesars. It was one of a string of forts, within a day’s march of each other, built at a time of increased insecurity in the Roman Province of Arabia. There were also watchtowers between the forts, so that signals could be sent rapidly from one to another should troops be needed.
Qasr Bshir is almost square in shape, with the longest side, which has the main entrance in the middle, on the south-west. The central courtyard was surrounded by rooms on two levels, the lower ones with mangers built into the walls - perhaps an indication that the fort was a base for a cavalry unit. The upper rooms were probably occupied by soldiers. At each of the four corners stands a square tower, three storeys high, in one corner of which a square spiral stairway leads to the upper floors.
The fort was well supplied with water - three cisterns have been found outside the walls, and there are two cut into the ground in the central courtyard. Also, about 500m to the south-west is a large reservoir, also Roman in date. It is still in use, providing local farmers with water for their flocks.