Caves and potholes in Zona volcànica d'Olot

The zona volcànica d’Olot, protected as a Parc Natural, is the best-preserved volcanic area in the Iberian Peninsula, with dozens of volcanic cones such as Croscat or Santa Margarida. The volcanic materials (basalts, scoria) generate caves of a very different type from the usual calcareous karst – lava tubes are the most characteristic example – cataloged as one of the most singular geological curiosities in the catalog.