The
Vexin is a historical county of northwestern
France. It covers a verdant plateau on the right bank (north) of the
Seine comprising an area east-to-west between
Pontoise and
Romilly-sur-Andelle (about 20 km before Rouen), and north-to-south between
Auneuil and the Seine near
Vernon. The plateau is crossed by the
Epte and the
Andelle river valleys.