Cergy-Pontoise is a new town and an agglomeration community in France, in the Val-d'Oise and Yvelines departments, northwest of Paris on the river Oise. It owes its name to two of the communes that it covers, Cergy and Pontoise. Its population is 206,654 (2017), in an area of 84.2 km2. Created in the 1970s, it became an agglomeration community in 2004.