Qasr Al-Hallabat, 30 km from Zarka and 60 km from Amman, is perhaps one of the most representative and important sites in the Near East to understand the socio-political and cultural changes that took place in the transitional period from Late Antiquity to Early Middle Ages that gave birth to Islamic culture. It is also one of the largest of the Umayyad Desert Castles.
Originally Al-Hallabat was a small Roman fort built to protect the Via Nova Trajana, the Roman road stretching from Bosra to Aqaba was established after 106 A.D. This fort was part of the Limes Arabicus. It was enlarged and transformed into a fort with four corner towers in the fourth century AD., probably under Diocletian. It was heavily damaged in an earthquake in 551 AD, being heavily transformed afterwards into a monastery and a palace.
The main building is 44 meters on a side, with four large rectangular corner towers, originally three stories high, with narrow slit windows. The northwest corner of the castle incorporates a smaller and older fortress consisting of a central courtyard and cistern, surrounded by rooms.
An adjacent rectangular mosque, the first building on the way from the visitor’s centre, contains inscriptions dated stylistically to the first century of the Islamic era, between the middle of the seventh and the middle of the eighth century. A small but stylish Umayyad bathhouse, now known as Hammam As-Sarah was built about two kilometres east of the castle and was similarly decorated in fine marble, mosaics and painted plaster. West of the castle, the Umayyads built or rebuilt at least five cisterns and a huge water reservoir.
Excavations and clearance work inside the castle uncovered a total of 146 Greek inscriptions as well as two others in Nabataean and one in Safaitic, all engraved on regularly cut basalt stones. The Greek inscribed stones belong to an edict issued by the Byzantine Emperor Anastasius (AD 491–518) for the administrative and economic re-organisation of Provincia Arabia. These inscribed stones were brought from a nearby settlement and re-used as a building material during the Umayyad.
Originally a Roman fortress constructed under Emperor Caracalla to protect its inhabitants from Bedouin tribes, this site dates to the second and third century AD, although there is trace evidence of Nabatean presence at the site. It was one fort of many on the Roman highway, Via Nova Traiana, a route that connected Damascus to Aqaba. However, by the eighth century, the Umayyad Hisham ibn Abd al-Malik ordered for the Roman structures to be demolished to redevelop this military site and its neighbouring territory to become one of the grandest of all Umayyad desert complexes.
Guided by the extant plan, he incorporated a mosque (found 15 meters from the southeast of the main structure), a complicated water system including five cisterns and a considerably large water reservoir, and a bathhouse. Furthermore, situated to the west of the palace remains an enclosed structure probably used for agricultural purposes such as cultivating olive trees and/or grapevines.
While the only one-layered stone footprint of the agricultural structure still stands today, three wall sections of the mosque, including the mihrab in the southern wall, remain intact. The main palace is constructed of black basalt and limestone and has a square floorplan with towers at each corner. Grand in stature, the principal structures were further enhanced with decorative mosaics depicting an assortment of animals, detailed frescoes and highly crafted stucco carvings.