Val-d'Oise

Département in the Ile-de-France region of France; area 1,248 sq km/482 sq mi; population (1999 est) 1,105,500. It is situated northwest of Paris and north of the confluence of the rivers Seine and Oise, where the plateaux of Vexin and the Plaine de France are bisected by the River Oise. Agricultural production ranges from intensive market gardening to large-scale arable cultivation. Important industries are located on the northern margins of Paris and in the Oise valley, and include metal works, machinery, motor vehicles, and high-tech and service industries. The administrative centre is the new city of Cergy-Pontoise.

Val-d'Oise was created in the administrative reforms of 1964. Major road, rail, and water routes cross the département, which functions increasingly as a part of greater Paris.