The surprising depths of Casares

The lower part of the Pozo de Benito in the cave.
The lower part of the Pozo de Benito in the cave. / C. M.
  • The local GES is exploring a chasm which is 105 metres deep and has caves and galleries totalling 307 metres in length

Casares may be located at quite a high altitude above sea level, but it also has some impressive depths. There are some steep inclines around the village and, from work carried out in the area by the subterranean exploration association known as the GES, we now know that it is home to one of the deepest chasms in Andalucía, called the ‘Sima de Los Casteses’. It is located in the Sierra Crestellina, in the area known as Las Herrizas de Matagallar.

This pothole goes down to 105 metres at its deepest point, and it is 370 metres in length. It was originally found in the 1980s by the GES group in Estepona, but as time passed it was forgotten. Nobody could even remember where the entrance was.

In mid-2016, thanks to Ana María Pavón, Benito Trujillano and brothers José and Pablo Delgado, all of whom own land near the site, potholers from Casares were able to enter the cave system to carry out detailed topographic work.

The support of the landowners was so helpful that the group decided to call the chasm Los Casteses, because that was the nickname by which the Delgado brothers’ family used to be known in the past.

Jorge Romo, a member and the secretary of the GES in Casares, says that the first group from Estepona only went down to a depth of 80 metres. When the new team tried to explore the site recently, they had to replace all the installations with stainless steel elements first, because “corrosion had rusted everything our colleagues from Estepona had placed there,” he says.

After that, these experts used latest-generation lasers to measure the chasm and were then able to use IT programmes to produce an immediate representation of the measurements taken above ground, including a 3D one of the cavity. They were also able to verify its satellite coordinates.

Jorge explains that the system contains several vertical sections connected by galleries and passageways. Inside, it is calcareous and there are stalagmites. “There is quite a considerable amount of water in the cave, even in the summer, because it leaks from the surface. There is even some in the deepest parts,” he says. The cavity can be visited, he warns, but it is so difficult that it is only suitable for people with previous experience.

This is the nearest cave system to Casares, and is only 20 minutes away from the village. There are others in the Sierra de la Utrera, but they are not as close. Jorge believes this detailed survey of the Sima de Los Casteses will be of great interest to groups of potholers and adventure tourists.

After the summer the GES plans to return to explore further. Last time they found a new gallery which led to a new well. Jorge estimates that in places the pothole system could be at least 30 metres deeper than expected. Others in the area will also be inspected from above ground, with the aim of drawing up a catalogue of existing cavities within the perimeter of the Sierra Crestellina.