09/28/2026
Win-Timdouine Cave is located beneath the Tasroukht Plateau in Morocco’s Western High Atlas Mountains, northeast of Agadir. More than 19 kilometres of passages have been documented within the limestone, making it Morocco’s longest known cave system. It also contains the longest known underground river in Africa, an unusual feature in a region characterized by a semi-arid climate.
Water enters the system as rainfall filters through fractures and openings in the limestone of the plateau above. Studies of Win-Timdouine have shown a close relationship between rainfall, water moving through the cave, and the surrounding groundwater. The cave forms part of a larger karst aquifer that supplies freshwater to the region, demonstrating the important role cave systems can play in storing and transporting groundwater.
Stalagmites within Win-Timdouine also preserve a record of past environmental conditions. Changes in their chemistry and growth can be used to reconstruct variations in rainfall over thousands of years. Research from the cave has contributed to our understanding of the African Humid Period, when a stronger monsoon brought substantially more rainfall into northern Africa and parts of the Sahara supported lakes, rivers and vegetation. Win-Timdouine is therefore not only a record of the water moving through the landscape today, but also of major climatic changes that occurred thousands of years ago.