The Asperillo Cliff is a system of fossilized dunes that extend along twelve hectares of coastline between the beaches of Matalascañas and Mazagón. It is a coastal formation with its own geomorphological and ecological characteristics, featuring a sandy cliff formed by the aeolian and alluvial sedimentation of sands, with intercalations produced by clays, organic matter, and other materials. These cliffs are known as “cabezos” and are formed by different aeolian layers, with the oldest materials estimated to be between fourteen and fifteen thousand years old. The various layers were deposited, and later, terrestrial forces raised them more than 100 meters. The darker layers, due to the accumulation of organic matter corresponding to peat, can be observed, while in some sandy areas, an orange color can be seen caused by the iron oxide carried by groundwater. The very limited vegetation existing in the area stands out due to the harsh coastal conditions. Species such as the spur-thighed tortoise, sand boa, Iberian lynx, and mongoose inhabit the area. On November 23, 2001, the Andalusian Regional Government declared an area of this cliff, covering 11.85 hectares, a natural monument, recognizing its high geological and ecological values.