Ulldecona castle (cat. Castell d’Ulldecona) is a fortified complex of Ulldecona (Montsià, Tarragona province, Catalonia, Spain), declared a cultural heritage of national interest. It stands above Puig del Castel, a small hill that forms part of the Serra Grossa. Located on the left bank of the Senia River, it is the site of the current political and administrative border between Catalonia and Valencia. The fertility and wealth of the land contributed to the fact that this place over time became a strategic zone of control over the territory from the Iberian period to the Middle Ages.
The fortress is largely the work of the Order of St. John of Jerusalem. It was the seat of the chief hospitaller order of the Ebro lands after the exchange of the Castilian Amposta Ramon de Ribelles with King Pere el Gran in 1280.
After the Christian conquest of the lands south of the Ebro in 1148, the castle passed to the Moncada family of Tortosa. In 1173, the castle and land were transferred to the Order of St. John in Jerusalem. In 1178, Alfonso I returned it to the Hospitallers.
The fortified complex is located on the southwest side of the village, close to the Ulldecona-la-Senya county road. It currently consists of a round tower and an old church, as well as ruins surrounded by a perimeter wall. This wall, approximately 1 to 1.5 m thick, has been partially preserved in the northern sector, where it reaches a maximum height of 3 m.
The castle is a 20-minute drive from Tortosa.
GPS coordinates: 40 ° 35 ′ N, 0 ° 26 ′ E