Mérantaise

The Mérantaise is a small river in southern Île-de-France (France), left tributary of the Yvette, which is a tributary of the Orge. It is 14.3 km long. Its source is in Voisins-le-Bretonneux, near Versailles, in the Yvelines department.

Geography
The Yvette crosses the following départements and towns:
 * Yvelines department : Voisins-le-Bretonneux, Magny-les-Hameaux,
 * Essonne department : Saint-Aubin, Villiers-le-Bâcle, Gif-sur-Yvette