The Orne is a Norman coastal river that crosses the eponymous department to which it gave its name in 1790 and that of Calvados before flowing into the English Channel. Some 105.3 miles (170 km) long, it is the second longest river in Normandy after the Seine. On its course, it receives fourteen tributaries, especially on its left bank, due to the presence of the Massif Armoricain. The Orne crosses several municipalities that have taken up its name such as Fontenai-sur-Orne, Sainte-Croix-sur-Orne, Saint-Aubert-sur-Orne, or Saint-Philbert-sur-Orne.