Assiette illustrant le département de Seine-et-Oise, Château de St Germain (sic], 1826-1827 (Voyage pittoresque de la France, op. cit., t. I, [vol. 5), 1784, pl. 76, bas).
Seine-et-Oise (French pronunciation: [sɛn‿e waz]) is a former department of France, which encompassed the western, northern and southern parts of the metropolitan area of Paris. Its prefecture was Versailles and its administrative number was 78. Seine-et-Oise was disbanded in 1968 as part of the reorganisation of the departments of the Paris metropolitan area. The newly created Yvelines department inherited the 78 number.