Riaño is a former small municipality located along the Esla River in the mountains of the province of León, in the autonomous community of Castile and León, northern Spain. The village was across the river from Peak Gilbo. Located 3650 feet above sea level, it is in the Cantabrian mountains near the foothills of the Picos de Europa.
Due to planned construction of a dam and reservoir in the 1980s, for flood control and generation of hydroelectric power, the village and its lowlying farmland were to be submerged, as were six other villages in the associated dam project. The residents were relocated to New Riaño, built as a replacement higher above the reservoir waters.  In 2010 the village had 532 residents.
Noted residents and natives
- Imanol Arias, film actor