The Negev Desert covers more than half of Israel, over some 13,000 kmē (4,700 sq mi) or at least 55% of the country's land area. It forms an inverted triangle shape whose western side is contiguous with the desert of the Sinai Peninsula, and whose eastern border is the Arabah valley.

The Negev is a rocky desert. It is a melange of brown, rocky, dusty mountains interrupted by wadis (dry riverbeds that bloom briefly after rain) and deep craters. It can be split into five different ecological regions: northern, western and central Negev, the high plateau and the Arabah Valley.