To appreciate Mauritania you need to know a bit about the Sahara which occupies most of the country. The Sahara Desert is a vast region that extends from the Atlantic Ocean in the west to the Red Sea in the east, and from the Mediterranean in the north to a semi-desert zone in the south called the Sahel. It is characterized by extreme aridity. In the Sahara it is possible to drive for three days at 175 kilometers a day and not see any vegetation or animal life whatsoever - vast areas, totally devoid of life, larger than the state of Oregon. In July temperatures in the shade typically reach 45 C or 113 F and it is not unusual to go into the 50's on hot days.
Oases routinely go a decade or two without any rain at all.
Farafra in Egypt received rain in 1945 and not again until 1973. Geological features of the Sahara, according to Mr. Glen, include things you just t don't see every where else, particularly on such a grand scale. It is the last one that I find fascinating. Dunes of all sizes can be found, some stationary enough to be used for navigation, others relentlessly on the move, engulfing anything in their path. For example, the Great Erg Occidental, one of the smaller sand seas in the Sahara, extends for 450 kilometers without a break or any sign of plant or animal life.