Caves and potholes in Conglomerate terrain

Conglomerates are detrital sedimentary rocks made of rounded pebbles cemented in a matrix. When the cement is limestone, a peculiar karst of caves and tafoni develops, as at Montserrat or Sant Llorenç del Munt.

The catalogue records 1069 cavities in conglomerates, of which 739 are caves and 330 pits. Together they total 59902 metres of length and reach a maximum depth of 328 metres. The longest cavity is the Cova Cuberes, at Serradell (Conca de Dalt), with 13513.15 metres of length and 328 metres of vertical drop. Other cavities notable for their length are the Cova de l'Espluga, at 3590 metres; the Botet de Casa Rei, at 1579 metres; the Forat del Toscà, at 1416 metres; and the Coves del Salnitre, at 958 metres.

Among the deepest cavities are the Cova Cuberes, at 328 metres; the Avenc Montserrat Ubach, at 202 metres; the Pou de Costa Dreta, at 148 metres; the Avenc de les Rovires, at 126 metres; and the Pouetons de les Agulles, at 125 metres.