Scheldt (skĕlt) [key], Du. Schelde, Fr. Escaut, river, c.270 mi (435 km) long, rising in N France and flowing generally NE across W Belgium and into the North Sea through the Western Scheldt (De Honte) estuary, SW Netherlands. It receives its chief tributary, the Lys, at Ghent (Gent). Navigable for most of its length, the river is connected with a dense network of canals in N France and Belgium. From the Peace of Westphalia in 1648 until 1863 (except during the Napoleonic period), the Netherlands possessed the right to close the Scheldt estuary and thus had a stranglehold over the port of Antwerp.