Nearly all the caves in the Murcia Region are formed by limestone or dolomite, which results in the large number of cavities catalogued. The longest-stretching cave is the Cueva del Puerto, in Calasparra, in which some 5 kilometres have been mapped. Some of the caverns are open for guided tours; the rest can be explored by groups of cavers accompanied by guides.
As far as vertical drop is concerned, the Region's deepest cave is the Destapada, in Isla Plana (Mazarrón), which goes down 230 m.
Others of note are the Torreta (-175 m), in the Revolcadores massif; the Buitre (-106 m), in the massif of the same name (Caravaca); the Talayón (-152 m), in Lorca; and the Caneja, near Barranda, which is 220 metres long and 99 deep.