Most of Saudi Arabia is a desert. A long mountain chain runs the entire length of the Eastern Saudi Arabia, gradually becoming higher as it reaches south towards Yemen. Almost half of the country comprises of the Rub’al-Khali, or the Empty Quarter, which is the largest sand desert in the world. Most of the central and northern region of Saudi Arabia is a gravelly desert plain. To the north west of Saudi Arabia lies Nafud, Arabia’s second greatest sand desert that is linked to the Empty Quarter. The Eastern Province of Saudi Arabia is a low-lying area that has a number of sabkhas (salt flats). Its main geographical feature is the vast Al-Hasa oasis, in the midst of which lies the town of Hofuf.

Desert scrub and tamarind trees grow in the country. After the winter rains, plants such as desert chamomile, scarlet pimpernel, heliotrope and wild iris are a common sight in the desert. In the forested areas of Asir, various evergreens grow.

Despite the bareness, there is considerable life in the desert, especially after the winter rains. Small animals such as lizards, porcupines, hedgehogs and rabbits can be seen. Wild baboons are found in the Asir region. Of course, the "ship of the desert" is visible in plenty.