[custom_adv] The Rig Jenn is a vast area of sand dunes in the middle of Dasht-e Kavir, central desert in the border region of the Semnan and Isfahan provinces. [custom_adv] It was not travelled by the old caravan travellers, who believed it is a place where evil spirits live. [custom_adv] Even today some in the neighbouring towns and villages believe this. Sven Hedin, the famous desert explorer avoided this area in his 1900s explorations to deserts. [custom_adv] The Austrian geographer Alfons Gabriel crossed the southern 'tail' of it on his way from Ashin to Arusan in the 1930s. [custom_adv] A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. [custom_adv] The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation. About one-third of the land surface of the world is arid or semi-arid. This includes much of the polar regions where little precipitation occurs and which are sometimes called polar deserts or "cold deserts".