The Sudans Nile within the Sudans has no significant tributaries. The amount of rainfall increases towards the south. In the north there is the very dry Nubian Desert; in the south there are swamps and rainforest. The Sudans’s rainy season lasts for about three months (July to September) in the north, and up to six months (June to November) in the south. The dry regions are plagued by sandstorms, known as haboob, which can completely block out the sun. In the northern and western semi-desert areas, people rely on the scant rainfall for basic agriculture and many are nomadic, travelling with their
Desert castles the production of olive oil. The generic term, "desert castle," is not ideal, since it artificially separates similar "qusur" according to their location. Jordan possesses at least one urban Umayyad "qasr" on the Citadel Hill of Amman. While the majority of "qsar" are located Jordan, examples can also be found in Syria, the West Bank and Israel, either in cities (Jerusalem, Ramla), 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