The bottom of Chott el Djerid is located between 10 and 25 meters above sea level. Roughly in the shape of a tadpole, with a width of 20 km (12 mi) at its narrowest point, it reaches 250 km (160 mi) in overall length. At times, parts of it appear in various shades of white, green and purple
It is the largest salt pan of the Sahara with a surface area of over 7,000 km (some sources state 5,000 km). Due to the extreme climate with annual rainfall of only 100 mm and temperatures reaching 50 �C, water evaporates from the lake. In summer Chott el Djerid is almost entirely dried up, and numerous fata morganas occur.
During winter, a small tributary of water can be seen discharging into the lake
