Ruins of a fortress, (XIX century) on the dam of Xerta. This fortification currently remains in rubble and only ordinary masonry walls are standing, with some ashlars on the bases (more reinforced) and corners. The walls, with loopholes, form a small and narrow enclosure. The place is a real nest of eagles, very difficult to access, since there is no road or path and is located at the highest level of the Coll de Som (251 m), from where you can enjoy a wide panoramic view of the Ebro valley, over the Azud of Xerta-Tivenys. The interior of the walls contains numerous graffiti with letters, of which it has not been possible to determine its meaning. In the front area of the castle, a parapet has been erected with bricks from the castle, from which its origin cannot be determined.

Strategic place where some place the old medieval village of Som. At present, only the ruins of the fortifications and the observation point over the river and the valley, from the 19th century (Carlist War) and the 20th century (Civil War), can be seen. This hill was used as a magnificent observatory by the Autonomous Group of the Ebro, later Army of the Ebro, from April 1938 to January 1939. The vertex was also used as a deployment boundary between the different military units located on the front line of the Ebro on its left bank.