Caves of Horta de Sant Joan

Horta de Sant Joan, a municipality in the comarca of Terra Alta, brings together 38 catalogued cavities: 15 pits and 23 caves. The total length of the inventoried cavities is 1905 m and the maximum depth reached is 65 m. The lithologies present are limestone (28 cavities), conglomerate (6) and dolomite (4).

Among the longest cavities, Cova del Conill stands out, with 260 m of length and an underground river with a flooded shaft and a terminal sump; Avenc dels Quatre Pous, a fissure 28 m deep and 159 m long; and Cova d'en Domingo Grau, 156 m long, with an entrance of 1.30 x 1.20 m, galleries, a chamber with lithogenic concretions and a gour, a small 6 m pit and a total drop of 16.20 m (-6.70; +9.50). Also listed are Avenc de la Vinyeta, 35 m deep and 121 m long, and Cova Cabrera, 92 m long.

As for depth, Avenc del Cingle reaches 65 m, followed by Avenc Lo Fornàs with 55 m. Avenc de les Foies de Corretjà and Avenc Negre are each 41 m deep; the first was explored by the ERE del CEC in January 1976 and the second is located to the SW of the Mola dels Atans, in the upper area of the barranc dels Cubars. Avenc de la Mosca, 36 m deep, at the head of the barranc dels Covards, was discovered and explored in 1978 by members of the DER – Reddis (Reus).