Nogent-le-Rotrou is a commune in the Eure-et-Loir department in northern France.It is a sub-prefecture and is located on the Huisne River, 56 kilometres west of Chartres on the RN23 and 150 kilometres south west of Paris, to which it is linked by both rail and motorway. It was the former capital of the Perche with the count living in the impressive medieval Château Saint - Jean which still dominates the town from a plateau of the same name.