The Columbrete Islands. Formed by four small groups of islands of volcanic origin and on a clear day, they can be seen from Peñiscola. Each group of islands take their name from the largest island in each group, so we have: La Grossa, la Ferrera la Foradada and el Carallot. Their depth in the water reaches 80 metres and these islands represent an archipealago of high ecological interest in the meditterean. Daily excursions leave from the port of Peñiscola.