Eure River, river in northern France, a left-bank tributary of the Seine, with a length of 140 miles (225 km). From its source in the Perche Hills, Orne département, at an elevation of about 800 feet (240 m), to its confluence with the Seine River above Rouen at Pont de l’Arche, it flows chiefly through agricultural and wooded regions, receiving numerous tributaries, including the Blaise, the Avre, and the Iton. It flows southeast from its source to the area south of Chartres, Eure-et-Loir département, and then turns sharply north, passing through the city of Chartres below the cathedral, which is located on high ground on the left bank. Continuing its northern course, the Eure flows through Maintenon, Dreux, and around Anet, veering northwest. After crossing Pacy-sur-Eure, in Eure département, it flows almost parallel to the Seine for more than 20 miles (32 km) before separating into several branches and flowing through the town of Louviers.