A mountainous area in south-east Syria, just along the Israeli border. Over 6,000 feet (2,000 metres) high, they are of enormous strategic importance as they make possible the military control of northern Israel up to Haifa and beyond, as well as southern Syria up to Damascus. They were occupied by Israel after the Six Day War from 1967, the population of around 130,000 was expelled, and new Jewish settlements were founded to claim the area permanently for Israel. They are an important source of water, and provide 50 per cent of the water supply for Israel's deserts. The Heights were annexed in 1981, though this was not internationally recognized. After Israel's recognition of the PLO, their occupation by Israel remained the biggest stumbling block to a lasting peace with Syria. Negotiations were taken up in 1999, but ended inconclusively following the breakdown of the Oslo Accords and the Wye Agreement. From the mid-1990s, the Israeli government encouraged Jewish settlers to move to the Golan Heights. By 2006, around 20,000 Jewish settlers lived next to 20,000 Arabs.