 Cherbourg-en-Cotentin is bordered by the sea.The construction of the port of trade, from 1769, accompanied by the diversion of the (the mouth of which was located at the current exit of Port Chantereyne) and the Trottebec (from the territory of Tourlaville) gathered in the "canal de retenue", along the "Avenue de Paris" and "Rue du Val-de-Saire".The streams of the Bucaille and the Fay, which watered the "Croûte du Homet", disappeared in the 18th century during the construction of the military port.