The Sile (Venetian: Sil) is a 95 km river in the Veneto region in north-eastern Italy. Its springs are in the municipality of Vedelago in the Province of Treviso. It flows into the northern part of the Lagoon of Venice at the mouth of the River Piave Vecchia. It receives the waters of its tributary, the Botteniga, at Treviso.
Some of the rivers in the plain of the Veneto come from springs in the nearby Alps, while others have groundwater springs in the plain. The Sile originates in the plain and therefore it is a short river. Its springs are in the area of Albaredo, Casacorba and Cavasagra in the municipality of Vedelago. The fontanasso dea Coa Longa is considered to be the main spring. Two initial branches join at Morgano. The river has an initial west-east windy course which passes through or by Santa Cristina, Quinto di Treviso, Canizzano and Treviso. In Treviso it turns in a northwest-southeast direction towards the lagoon and passes by Silea, Casier, Cendon, Lughignano, Sant'Elena, Casale sul Sile, Quarto d'Altino, Trepalade and Portegrandi.