The Tena Valley (in Aragonese Bal de Tena ) is a Pyrenean valley located in the Aragonese region of Alto Gállego (crossed by the Gállego river from north to south). It borders with the French valley of Ossau and access to France is through the Portalet d’Aneu pass . The southern limit is found in the Foz de Santa Elena which separates it from Biescas.
It is one of the largest and most populated valleys in the Pyrenees with an area of about 400 km² and mountains range from 600 meters of altitude in its lowest part to over 3000 m in many of its peaks (Balaitus, Gran Facha, Argualas or the Picos del Infierno). There are also two large reservoirs: Lanuza and Búbal.
