Over the years, the differnt owners of "the Domaine de Villelongue" created an ornamental park, which is really an arboretum, around the former abbot's mansion which had become the owners' residence. American strains of trees : séquoias, taxodium distichum, magnolias which were very fashionable in the 19th century,cedars and many other species of tree have grown on the banks of the Vernassonne. These trees are very lush thanks to generous quantities of water in this paet of the valley. It seems that this irrigation system dates back to the Cistercian monks who knew the art of building canals to supply the grounds of their abbeys with water.