The first caving expedition in Spain was carried out in this vertical chasm in 1841. It is located on the slopes of the Picacho de la Sierra de Cabra. It appears mentioned in Don Quixote and in other works by Miguel de Cervantes, who lived in the town of Cabra. It has an average width of about 20 meters and a depth of -116 meters, up to its base, but it has an additional narrow gallery that leads to the Sarcophagus room, located at -131 meters.