Desert castles The Umayyad desert castles, of which the desert castles of Jordan represent a prominent part, are fortified palaces or castles in what was the then Umayyad province of Bilad al-Sham. Most Umayyad "desert castles" are scattered over the semi-arid regions of north-eastern Jordan, with several more in Syria, Israel and the West Bank (Palestine). Brief description : The Umayyads erected a number of characteristic palaces, some in the cities, but mostly in the semi-arid regions, and some along important trading routes. The castles were built roughly between 660 and 750 under the Umayyad Caliphate, which had made Damascus, now in Syria, their new capital in 661. After the Abbasid Revolution of 750, the capital moved to the newly-built Baghdad and some of the buildings were never completed. The typical desert castle is more than a single residence; rather it is a compound of various building including a substantial main residence along with other buildings such as a hammam (bath-house), storage areas and other agrarian structures and possibly a mosque, all within a large enclosure. Desert castles are typically situated near a wadi or seasonal water course. The inner part of the main residence typically consists of two-storeys, arranged around a central courtyard. The main residence is often richly ornamented with mosaics, frescoes and stucco reliefs. Archaeologists have investigated the role of these desert castles, with the traditional view that they served as country estates or hunting lodges for the use of aristocratic families during the winter season. However, recent scholarship has suggested a much greater diversity of roles, including as agricultural estates or military forts. The complex at Qasr al-Hayr al-Gharbi (Syria), for example, sits within a vast agricultural estate and the buildings include structures associated with the production of olive oil. Layout and decoration : With a few exceptions, the desert castles conform to a common template consisting of a square structure similar to Roman forts ("castra") as their main building, typically boasting an elaborate entrance. Other buildings in the complex would include a hammam (bath house), a mosque, and often an agricultural enclosure (walled areas for animals, dedicated buildings for processing produce such as olive oil), and a water reservoir or dam. The interior rooms of the main structure were ornately decorated with floor-mosaics, and wall paintings featuring designs that exhibit both eastern and western influences. Some of the desert castles, for example Qasr Hallabat or Qasr Burqu', are rebuilt from remains of earlier Roman or Ghassanid structures; others are new constructions . Purpose: The function and use of the buildings are today not entirely clear, and scholarship has suggested that they might have served a variety of defensive, agricultural, residential, recreational and commercial purposes. The earliest researchers, such as Musil and Lammens, suggested that desert castles were primarily used for recreational purposes: to escape bad air associated with city living to escape epidemic outbreaks; to indulge hedonic pleasures or for use as hunting lodges. Yet other scholars, investigating the geographic distribution of desert castles have noted that they are principally situated along the silk road or pilgrimage routes and may have operated as a type of caravanserai. Given the variety observed in the archaeological record, it is unlikely that one single theory can explain the range of purposes of all the buildings. These functions include fortresses, meeting places for Bedouins (between themselves or with the Umayyad governor), badiyas (retreats for the nobles) or caravanserais. A proliferation of desert castles appeared around the same time as the number of caravans increased substantially. Many seem to have been surrounded by natural or man-made oases and to have served as country estates or hunting lodges, given that hunting was a favoured pastime for the aristocracy. The generic term "desert castle" is not ideal, since it artificially separates similar quṣur according to their location. Jordan possesses at least one urban Umayyad qaṣr: the Amman Citadel. While the majority of quṣur are located in Jordan, examples can also be found in Syria, the West Bank and Israel, either in cities (Jerusalem), in relatively green areas (al-Sinnabra, Khirbat al-Minya), or indeed in the desert (Qasr al-Hayr al-Gharbi and Qasr al-Hayr al-Sharqi, Jabal Sais, Hisham's Palace). The more isolated "desert castles" built in arid regions, are chiefly located on the ancient trade routes connecting Damascus with Medina and Kufa or adjacent to a natural oasis. Their location along major routes and next to the very scarce water sources seems to indicate that they enabled the Umayyads to control the roads militarily, monitor and tax the seasonal movement of people and their livestock, and not least, impress travellers and local tribes with lavish displays of monumental architecture, baths and ponds in the middle of an arid landscape. Most of the desert palaces were abandoned after the Umayyads fell from power in 750, leaving many projects uncompleted and others were left to decay.