Dyle (French) or Dijle (Dutch) is a river in central Belgium, left tributary of the Rupel. It is 86 km (53 miles) long. It flows through the Belgian provinces Walloon Brabant, Flemish Brabant and Antwerp. Its source is in Houtain-le-Val, near Nivelles.
The most important towns along the Dyle are (starting from the source) Ottignies, Wavre, Leuven and Mechelen. The latter is often called the 'Dijlestad' (Dyle City). Main tributaries of the Dyle are the rivers Demer (in Werchter, Rotselaar municipality), and the Zenne at the Zennegat, furthest outskirt of Mechelen, where also the canal Leuven-Mechelen connects. A few hundred metres downstream, the confluence of the Dyle and the Nete at Rumst forms the river Rupel which 12 km further comes into the Schelde at which the Antwerp seaport is located. The Dyle used to be navigable for small ships from Werchter on, although nowadays commercial and pleasure navigation is limited to Mechelen, the upper locks at Mechelen being closed for navigation.