Administration
Pontoise is the official préfecture (capital) of the Val-d'Oise département, although in reality the préfecture building and administration, as well as the department council (conseil général), are located inside the neighboring commune of Cergy, which is regarded as the de facto capital of Val-d'Oise.
Pontoise is also the seat of the Arrondissement of Pontoise. The sous-préfecture building and administration, unlike the préfecture, are located inside the commune of Pontoise.
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