Pontoise is in the (95) Val d'Oise departement
Map of Pontoise in the Val d'Oise
Pontoise is in the Val d'Oise department of the Paris-Isle-of-France regionThe town is on the banks of the river Oise, hence the name Pont-Oise, the bridge over the river Oise. Now engulfed by the urbanisation of Paris.
The origins of the town were commercial, but with the repeated invasions beginning with the Normans, the population then decided to defend their town. Below the castle there is a mass of tunnels and cellars.
The Carmelites built a Carmel in 1605 and is still intact and working today.