Grotte e abissi nella grande unità geologica Depressió Central

The Depressió Central is a large sedimentary basin in inland Catalonia —the Ebro Depression— with gentle relief. Sandstones, conglomerates and gypsum predominate, with a discreet but locally notable karst, such as the Cardona salt massif. It contains 272 cavities, of which 251 are caves and 21 pits, with a total development of 13670 metres and a maximum depth of 187 metres.

Among the longest cavities are the Cova dels Meandres de Sal, with 4300 metres, the Cova de l'Espluga, with 3590 metres, and the Cova del Toll, with 1148 metres. As for depth, the Cova dels Meandres de Sal reaches 187 metres, followed by the Avenc d'Enconills, with 40 metres, and the Cova de l'Espluga, with 26 metres.

The recorded lithologies include sandstones, conglomerates, limestones, gypsum, salts and travertines. The unit contains 10 subunits.