A vast area of Oman is covered by the Rub’ al Khali, the largest expanse of sand in the world. This Arabic phrase means “the Empty Quarter”, and this desert stretches over a quarter of the entire Arabian Peninsula. Its enormous surface area (twice the size of Victoria) lies partly in the Sultanate and partly in neighboring Saudi Arabia and Yemen. One of the few areas on Earth not to have been fully explored, it was nicknamed the Desert of the Deserts by the explorer Wilfred Thesier.