Étang de Saint-Quentin
Agua
The Étang de Saint-Quentin, or pond of Trappes, with a surface of approximately 2.5 km², is the largest body of fresh water in Yvelines. It on in the perimeter of the new town of Saint-Quentin-in-Yvelines, in the commune of Trappes and Montigny-le-Bretonneux. The lake an important base of outdoor recreation.