Sweeping forests, tended by the département in cooperation with the State, offer vast areas of natural beauty far from the bustle of city life, while quality leisure facilities have been installed on hillsides in Cormeilles-en-Parisis and Sannois.
The Montmorency valley boasts any number of parks and gardens, a rigorous zoning protects farmland in the western part of the Plaine de France.Development in the Vexin, which lies in the western part of the département, takes place within the framework of a Regional Nature Park , with space reserved for high-technology businesses, laboratories and small business parks compatible with environmental priorities.Marines, Chars and Magny-en-Vexin are flourishing local centers with close links to neighboring regions.Finally, the architectural and artistic treasures of the Val d'Oise are known worldwide, and visitors make an important contribution to the local economy. Among the best known attractions are the abbey of Royaumont , the château and museum at Ecouen, sites which inspired the painters from the Impressionist school, the Château de Léry at Auvers-sur-Oise , the Château de la Roche-Guyon and the gardening museum at Villarceaux. Here, too, quality of life is the priority for the Val d'Oise, which offers a breath-taking choice of natural landscapes and greenery just a short distance from the capital.