Val-d'Oise is one of the 93 departments of metropiltan France, located in the
Île-de-France region. The department came into existence in 1968, following the division of the Seine-et-Oise department. The department is named after the Oise River, which flows through the province from northeast to southwest and is a right tributary of the River Seine. The Pays de France, an area of fertile plain traditionally used for agriculture, particularly cereals and sugar beet, based on its fine silty soils, is situated in the eastern part of the department. This region's size is continuously decreasing as Paris expands. Hauts-de-Seine lies to the department's south, Yvelines to the southwest, Eure to the west, Oise to the north, Seine-et-Marne to the east, and Seine-Saint-Denis to the southeast. Although the official préfecture of the department is Pontoise, located in the suburbs of
Paris, about 28 kilometres northwest of the city centre, the préfecture building and administrative offices are located in the neighbouring commune of Cergy.
The department is home to Charles de Gaulle Airport, partially situated in Roissy-en-France, a town in Val d'Oise. Other parts of the airport are located in the departments of Seine-et-Marne and Seine-Saint-Denis. The southernmost part of the department constitutes the Seine Valley and covers the entire Vallée de Montmorency.
Val-d'Oise boasts of a rich archaeological and historical heritage, but it is not a tourist destination often visited, perhaps overshadowed by the French capital. However, the department has several interesting places to visit, including La Roche-Guyon. This place features a
castle on top of a rocky hill and a twelfth-century château. L'Isle-Adam is another historic small town of the department situated on the bank of the River Oise. Auvers-sur-Oise owes its international fame to its landscapes and impressionist painters such as Charles-François Daubigny, Paul Cézanne, Jean-Baptiste-Camille Corot, Camille Pissarro, and Vincent van Gogh, who immortalized them. Enghien-les-Bains is a spa resort with a hot, sulfuric spring on the site of what was once Lake Enghien. Écouen features a fine château that houses the Museum of the Renaissance. Cergy-Pontoise is the new administrative capital created out of thirteen communes, quadrupling in population since the 1960s.