In front of environmental challenges widely connected to climate change and to recurring effects of the desertification, Africa and in particular Africa in the South of Sahara is condemned to make front. The  Green Great Wall (GGW) initiative, transcontinental project, under the umbrella of  Community of the Sahel-Saharan States (CEN-SAD) and African Union is an answer of Africa.

The Great Green Wall will be a multi-species vegetal belt 15 km wide that will link Dakar and Djibouti and stretch over a distance of about 7000 km. At the operational level, the individual countries involved with the Wall must delineate a forest band 15 km wide, in accordance with the conceptual chart of GGW alignment. This band must necessarily go through the Sahelian zone between isohyets 100 to 400 mm.

The Great Wall will form, as much as possible, a continuous band but may be rerouted if necessary to avoid obstacles (streams, rocky terrains, mountains and rock hills) or go through inhabited areas.