َ َ َ Al Ain is known as the "Garden City" (Arabic: ة َق ْن ِدحمٱ َة ْن ِيدم, romanized: Madīnat Al-Ḥadīqah, lit. 'City of The Garden')[1] of Abu Dhabi,[3] the UAE[4] or the Gulf,[5][6] due to its greenery, particularly with regard to the city's oases,[2] parks, tree-lined avenues and decorative roundabouts, with there being strict height controls on new buildings, to no more than seven floors,[9] and according to one author, an oasis around Al-Ain and Al-Hasa in Saudi Arabia are the most important in the region of the Gulf.[10] The city is located approximately 160 kilometres (99 mi) east of the capital Abu Dhabi, and about 120 kilometres (75 mi) south of Dubai.[11] The eastern region covers an area of approximately 13,100 km2 (5,100 sq mi). Oman lies to the east, Dubai and Sharjah to the north, Abu Dhabi to the west and the Empty Quarter desert and Saudi Arabia to the south. The topography of Al-Ain is unique and varies as one travels to the east. The ecologically important Jebel Hafeet ("Mount Hafeet"),[12] an outlier of the main Hajar range, is considered one of the monuments of Al-Ain, lying just to the south of the city. Rising to 1,100–1,400 metres (3,600–4,600 feet) in elevation,[2][13][14] Jabal Hafeet is one of the highest mountains in the country,[3] and has a number of ridges which stretch to the inner part of the city, two of which are Jabal An-Naqfah[15][16][17] (which touches AlAin Oasis),[18][19] and the Western ridge.[20][21] Sand dunes of varying texture that are tinged red with iron oxide lie to the north and east of Al-Ain.[citation needed] The city has a hot desert climate (Köppen climate classification BWh), featuring long, extremely hot summers and warm winters. In Al-Ain, the mean annual rainfall is 96 mm (3.8 in) and the average relative humidity is 60% (United Arab Emirates University, 1993). Low humidity in Al-Ain, particularly during the summers, makes it a popular destination for many people at that time of year. Boer (1997) classified the UAE climate as hyper-arid and divided it into four climatic regions: the coastal zone along the Persian Gulf, the mountain areas northeast of UAE, the gravel plains around Al Ain, and the central and southern sand desert. More rainfall and lower temperatures occur in the northeast than in the southern and western regions. The monthly average rainfall around Al-Ain was 100–120 mm (3.9–4.7 in) from the period 1970 to 1992.[citation needed] To the south of the city, near Oman, there is the man-made Lake Zakher, which resulted from the release of waste water from desalination plants.[22] Also in this region, to the east of Jebel Hafeet, lies the area of Mezyad, which has a border crossing with Oman, and is where the historic Mezyad Fort is located.[18][23]