evidence: The Syrian Desert, or Southeastern Desert, is a vast and sparsely populated region in southeastern Syria. It is the basin of the river Euphrates. It consists of the districts Ar-Raqqa (Arabic: الرقة), Al-Hassakeh (Arabic:الحسكة; Syrian Aramaic: ܓܨܪܛܐ; Kurdish: Hesiça), Deir az-Zur (Arabic: دير الزور) and parts of the provinces of Muḥafaẓat Ḥimṣ (Arabic: مُحافظة حمص), Muḥāfaẓat Ḥamāh (Arabic: محافظة حماة) and Rif Dimashq (Arabic: ریف دمشق). [...] - 4 Resafa — Archaeological site of the Byzantine city of Sergiopolis - 5 Qasr al-Hayr al-Sharqi — A castle (qasr) in the middle of the Syrian Desert, built by the Umayyad caliph Hisham ibn Abd al-Malik in 728-29 CE.