A hamada (Arabic, حمادة ḥammāda) is a type of desert landscape consisting of largely barren, hard, rocky plateaus, with very little sand. A hamada may sometimes also be called a reg (pronounced "rug"), though this more properly refers to a stony plain rather than a highland.
Hamadas exist in contrast to ergs, which are large areas of shifting sand dunes.
The world's largest hamada is the Hamada du Draa, in the northwest Sahara desert, between Morocco, Algeria and Western Sahara. Hamada areas form 70% of the Sahara desert.
Read more about Hamada: Formation