A demon has been the cause of some damage in the landscape of Les Planes! There is a stone marked with the footprint of the demon's horse (in Can Dou) and another rock that split in half (Roca de la Balma), although there are those who say that this was the work of lightning.

They also say that the Castle of Hostoles was demolished by a possessed devil when a coal miner who was looking after a newborn discovered that the child was the son of the devil. Another legend about the castle tells that there are underground passages that connect it with the old quarter of town, and that this allowed them to survive the siege by the Saracens.