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The littoral zone of the Safi coastline is characterised by different geomorphological forms of coastal cliffs cutting into alternating layers of clay and limestone outcrops. The cliffs undergo a wide range of erosional processes with landslides as the most significant mode of recession. A classification of these landslides was made using the typology of the mechanisms, materials and the state of activity. The cliff movements are triggered at the clay level, thus, it is necessary to determine their physical and mechanical characteristics in order to describe their geomechanical behaviour. The finer grain size distribution of the matrix reveals that the clays are misclassified and are ranging as silty clay loam. The Atterberg limits classify this formation as silt or clay of medium plasticity. The proportion of clay, the lithostatic pressure, and the slope are discussed as explanatory variables and expressed as indices. These measurable and descriptive geomorphological parameters can be used to explain the distribution of landslides, especially the rotational type. Statistical correlation in association with rotational slips indicates that the zones with high lithostatic pressure and significant value of the clay index are most affected by these instabilities. • The cliff coastline of Safi (Morocco) are composed of Jurassic, Cretaceous and Plio-Quaternary rocks. • Four landslides types are affecting these cliffs : rock falls, toppling, translational landslides, and rotational landslides. • Clays are, in presence of water, the trigger element of these landslides. The rotational ones are the most important. [ABSTRACT FROM AUTHOR]