The Gypsum Karst formations in Sorbas are in eastern Andalusia, at the far east of the Tabernas-Sorbas sub-desert corridor, the most arid region in Europe. Hidden in this apparently barren, arid land lies one of the most stunning places in Andalusia. It is an underground world carved out by the action of water over the ages on a large area of gypsum rock.

There are more than 1,000 caves, most of which are interconnected, and a spectacular, varied array of crystalline formations: stalactites, stalagmites, columns and corals. Their great educational and scientific value, along with their speleological interest, have made them one of the world’s most important gypsum karst areas, a real geological treasure.

The geological history of karst landscapes goes back six million years. At that time the Sorbas basin was filled with water from the Mediterranean. In a subsequent period, this sea became ever shallower, subject to high rates of evaporation, causing the precipitation of a section of gypsum more than 100 metres thick. When the sea withdrew definitively, the gypsum and other sediments remained on the surface, exposed to the slow but constant erosive action of rain water, producing this karst landscape of incredible beauty.

Rainwater can slowly dissolve gypsum rock, giving rise to an abundance of closed depressions in the surface. This is where the karst "windows" appear, the sink-holes and caves that connect the arid surface with the complex network of galleries underground. Water penetrates through these windows and continues its erosive, smoothing action, defining Spain's largest subterranean cave system and the world's second largest (discovered) in gypsum: the Cueva del Agua system, which is almost 8,500 long.

On the arid surface of the karst, vegetation has had to adapt to the harsh environmental conditions, developing ingenious strategies to obtain and retain water. Plants exclusive and endemic to this area live on the gypsum. They include the Sorbas daffodil (Narcissus torfilius) and the Sorbas spur, along with one of the most emblematic species of southeastern Spain (despite the name): the Greek tortoise. The rocky crevasses and banks so characteristic of this area are also the perfect habitat for the Eurasian eagle owl and Bonelli's eagle, while gaps in the large blocks of gypsum provide shelter for foxes, badgers, weasels and genets.

The Karst formations act as a huge sponge, collecting and storing all the rainwater, which then comes out through upwelling points, which are the springs. The biggest spring is Los Molinos, which wells up in the River Aguas canyon. The constant presence of water in this arid environment produces an oasis effect, generating a wetland of immense ecological value. Oleander groves, grasses, reeds and white poplars create riverine woodland that serves as refuge for a large colony of water birds: warblers, nightingales, kingfishers, etc. The water was also used by man, in now-abandoned water mills, to produce flour and oil from the surrounding cereal crops and olive trees, giving rise to the River Agua Mills village and vegetable gardens.

In and around this area there are various farmsteads that are now abandoned, such as El Tesoro and Marchalico Viñicas, and the aforementioned River Agua Mills, currently being renovated. All these are silent witnesses to a culture of subsistence farming and livestock rearing that has now died out. As with other parts of the province of Almeria that have been deserted, there was generalised human migration here throughout the 20th century.

The village of Sorbas is two kilometres from here and has a typical Moorish layout, with a network of steep, narrow streets. Its traditional crafts, ethnographically interesting fiestas, architecture and delicious, varied gastronomy will ensure you enjoy your visit.