Cergy

Cergy is a commune in the northwestern suburbs of Paris, France. It is located 27.8 km. (17.3 miles) from the center of Paris, in the "new town" of Cergy-Pontoise, created in the 1960s, of which it is the central and most populated commune.

Although neighboring Pontoise is the official préfecture (capital) of the Val-d'Oise département, the préfecture building and administration, as well as the department council (conseil général), are located inside the commune of Cergy, which is regarded as the de facto capital of Val-d'Oise. The sous-préfecture building and administration, on the other hand, are located inside the commune of Pontoise.

The name Cergy comes from Medieval Latin Sergiacum, meaning "estate of Sergius", a Gallo-Roman landowner.

When Cergy was selected to become the center of a "new town", it was only a village. The commune had only 2,895 inhabitants in 1968. It then started to develop very quickly, exceeding 10,000 inhabitants in the mid-1970s and then 20,000 in the early-1980s. It is in this decade that its growth was most spectacular, since the city exceeded 48,000 inhabitants in 1990. The increase continued since, but at a notably slower page, to reach 54,500 as of 2004 estimates.

Cergy is served by three stations on Paris RER line A and on the Transilien Paris – Saint-Lazare suburban rail line: Cergy – Préfecture, Cergy – Saint-Christophe, and Cergy – Le Haut.