Isolated in the Syrian desert, Qasr al-Hayr al-Sharqi stands approximately 97 km to the northeast of Palmyra and 64 km to the south of Rusafa. It was originally constructed by 728-9 under the caliph Hisham to be used as a retreat for the Umayyad caliphate. However after their decline in regional authority, the site was absorbed and embellished by the Abbasids under caliph Harun al-Rashid and remained functional until the 14th century.

Evidence of a complex water infrastructure system suggests that the site was comprehensive in scope. The remnants of this Umayyad city are encompassed by a large outer enclosure measuring some 7 sq km., probably reserved for gardens, animal husbandry, and other agricultural purposes. Within it the site includes two enclosures, one significantly larger than the other, and a bathhouse.

Built in stone layers, the smaller enclosure is supported by a total of twelve towers, four at each corner and all equidistant with the exception of two that immediately flank the main gate of the structure on the western façade. Its plan incorporates an entrance hall including a mihrab on its southern wall and a variation of narrow rooms surrounded by a portico that opens into a central courtyard featuring a cistern close to its center. This layout suggests that this structure most likely served as a khan; with the reception hall available as a place for prayer, commercial and animal storage space on the first floor, and accommodations on the second level for merchants.

The larger enclosure was also built of masonry with its interior walls erected in mud-brick over a stone foundation. Almost square in plan, each façade incorporates a central gate to the inside, each roughly identical in design and flanked by two supporting towers. Six other towers support each side, including one at each corner. Again, the plan is organized around a large, limestone-paved central courtyard, which includes a deep cistern that can hold slightly more than a quarter of a million gallons. In addition this enclosure incorporates a mosque in the southeast corner, residential areas, buildings for official administrative purposes, and an olive press.

Approximately 60 meters to the northwest of the smaller enclosure stood the bathhouse. It included a large hall approximately 20 by 15 meters, which featured two pools supplied by water jets, a room for changing with latrines nearby, a changing room for winter months, which was slightly closer to the warmer sections of the bathhouse. It also provided three hot rooms located near the furnace, and service areas including a place to store water.

Qasr al-Hayr al-Sharqi displays influences in construction from Syria and Iraq, in the breadth of its masonry work and in the use of brick throughout the complex, respectively.

Sources:

Creswell, K. A. C. A Short Account of Early Muslim Architecture, 149-164. Rev. ed. Allan, James W. Aldershot: Scolar Press, 1989.

Grabar, R. Holod, J. Knutstad and W. Trousdale. A City in the Desert: Qasr al-Hayr East. USA: Harvard Middle Eastern Monographs, 1978.