The ancient olive trees fields of Ulldecona, south of Montsià, make up the largest group of this type of trees in Catalonia. Almost two thousand trees aged between one thousand and two thousand years have been cataloged in this area. “Partida de Arion” is one of the most recommended points to visit these trees. There are about two hundred trees, including the “Fragua de la Arion”, which has 8 meters of perimeter and has been cataloged as a monumental tree by the Generalitat de Catalunya, the Government of Catalonia. It is a living natural heritage that is one of the most characteristic landscapes, historical and emblematic of the Ebro river territory.