Foggaras are underground galleries that collect the water that is in depth and transport to the surface. These nearly horizontal underground pipes carry water from the aquifer to the oasis, thanks to a slight tilt of one or two millimeters per meter. The gentle slope of the galleries slows the flow of water, avoiding friction with the ground and erosion. To make the system work foggaras, oases to be found in depressions or valleys, or at the foot of a hill, that is, below the water table. The oasis of Adrar are located below the plateau Tadmit where ground water emerges. This ingenious method gravity to transport water throughout the year. The materials used for the construction of the surrounding foggaras come: Blocks of stone are cut by a conglomerate of clay and straw, and palm trunks used to consolidate the underground galleries. The average length of the galleries is 2.5 km, and include vertical wells every 20 to 30 meters for ventilation and maintenance. Foggaras allow passi