The origin of Cueva de las Estegamitas is in water, the same as in most caves. But in this case, it was a kind of special water. The dissolution of the limestone rock occurred when groundwater that flowed through its interior trying to reach the sea, encountered salty seawater, of marine origin that, on a trip in the opposite direction, entered the interior of the rock mass.
This area in where the waters meet, and the transition between fresh and salty groundwater occurs, within the coastal karstic massifs, is known as the “mixing zone”. In this area, the water is particularly aggressive and capable of dissolving large amounts of rock, forming three-dimensional networks of caves with a maze-like morphology, such as those that are so common in the rocky cliffs of Malaga.
Although we do not know the exact moment in which the cave originated, we know that it was during a period in which the level of the Mediterranean Sea was considerably higher than today, probably more than 500,000 years ago.
After the origin of the cave, the sea level dropped, with different episodes of rising and dropping, tied to with warm and cold times, respectively, at a global level, until the sea reached its current position.
Today, Cueva de las Estegamitas is located well above the water table or upper limit of the groundwater that exists in the small karstic aquifer that forms the Cantal Chico. Inside we can find two types of water that continue to make the cave something “alive”: the dripping and oozing waters, on ceilings and walls, that start as rainfall and travel from the surface through small fractures and pores in the rock, and the water accumulated in small lakes or gours, more or less permanent, sometimes with the presence of floating calcite on their surface. Water of both types continues to do its geological work and create the wonderful speleothems that decorate the ceilings, walls and floors of this cave.