Grotte di Vallirana

Vallirana, a municipality in the Baix Llobregat, gathers 125 catalogued cavities: 97 pits and 28 caves. The group totals 4,088 metres of passage and reaches a maximum depth of 184 metres. The recorded lithologies are limestone, with 60 cavities, and dolomite, with 65.

The Avenc dels Esquirols is the longest cavity, with 430 metres, and also the deepest, with 184 metres; it has two entrances, shafts of 23, 8, 42, 9, 21, 16, 36, 18, 22, 13, 30 and 25 metres, and the directa, Montesinos and Esquirols routes. It is followed in length by the Avenc Pompeu Fabra, with 360 metres and 104 metres of drop, and the Esquerda Nº3 del Mas de les Fonts, with 220 metres and 53 metres of depth, the deepest and most complex of the group of fissures of the Mas de les Fonts.

Other notable cavities are the Avenc Abat Escarré, of 210 metres and 83 metres of depth, with two routes, explored by the ERE de l'AEC de Vallirana in the years 1969-1970 and with records of Troglocharinus Ferreri, and the Avenc Marcel, of 146 metres and 58 metres of depth, discovered in 1982 during the concreting of an electrical tower of FECSA.