The Tormes is a Spanish river, that starts in Prado Tormejón, in the mountain range of Gredos, Navarredonda de Gredos, province of Ávila. It crosses the provinces of Avila and Salamanca, ending at the Duero river, at a place known locally as Ambasaguas, after . This river is not able to provide the water supply to the population during summer and for this reason, the dam of Santa Teresa was constructed in 1960, with a capacity of to regulate and assure the water supply in summer, as well as to moderate high flows in winter. Also it has the dam of Villagonzalo and the Almendra Dam, near to where it joins the Duero.
- Length: 284 km
- Of great volume half: 42,43 ms³/s
- Surface of the river basin:
- Country that it crosses: Spain
- Mouth: Duero River at Fermoselle