Between 1936 and 1947, the American School of Prehistoric Research carried out a series of excavations at Mugharet el ‘Aliya, or “The High Cave,” located on Cape Ashakar just south of Tangier, Morocco. Overlooking the Atlantic Ocean, this prominent cave preserved one of the longest archaeological sequences known from the region, ranging from the Levalloiso-Mousterian (Middle Paleolithic, ca. 250,000–40,000 years ago) to Neolithic and even Roman times.
The first campaigns (1936–1938) revealed Neolithic and later material in the upper layers, including pottery, bone tools, and hearths. Subsequent excavations in 1939 and 1940, directed by Harvard’s Carleton S. Coon in collaboration with Ralph Nahon and Hooker Doolittle, pushed deeper into the cave deposits. Beneath the Neolithic lay rich Aterian horizons of the Upper Paleolithic (roughly 150,000–40,000 years ago), characterized by tanged points, bifacial leaf-shaped tools, and scrapers. These industries occurred in successive phases: an earlier facies dominated by bifacial leaf points, and a later one where classic tanged implements appeared in greater numbers.
Even deeper, the excavators uncovered traces of a Levalloiso-Mousterian occupation, which included stone tools made on prepared cores using the Levallois technique, a tradition commonly associated with Neanderthals. Fragmentary human remains were indeed found during the work, including a maxilla and an isolated tooth. Initially thought to be Neanderthal, later tests suggested that at least one belonged to a later Aterian context. This raised questions about the diversity of hominin groups occupying the Maghreb during the Late Pleistocene.
Geological studies carried out alongside the excavation showed that the cave’s deposits could be linked to fluctuations in sea level and climate. At several points, sterile layers of windblown sand and lagoonal sediments separated the cultural horizons, marking intervals when the cave was abandoned. Rockfalls and cemented sands further complicated the stratigraphy, but also preserved the sequence in remarkable detail.
By the 1947 season, the ASPR team, working with Moroccan and French colleagues, had confirmed that Mugharet el ‘Aliya recorded millennia of human presence. From Levalloiso-Mousterian beginnings to later Aterian toolkits, and finally to Neolithic and historic occupations, the High Cave offered a rare, continuous record of North Africa’s deep past. For the ASPR, Mugharet el ‘Aliya was not only a key excavation but also a demonstration of how stratigraphy, geology, and careful laboratory analysis could be combined to illuminate the long and complex human story of the Maghreb.