What is the Empty Quarter?

Southern Arabia contains one of the world’s bleakest deserts, which is visited only by the hardiest Bedouin nomads. Like all deserts, this is a place of extremes, and they must be prepared to risk hunger and thirst, and exposure to heat by day and bitter cold by night. The region is the Rub al Khali, or the Empty Quarter. Much of this 647,500 square km (250,000 square miles) is covered by drifting sand dunes up to 200 m (656 ft) high.