The Ossola (also Valle Ossola or Val d’Ossola) is an area of Italy situated to the north of Lago Maggiore. It lies within the Province of Verbano-Cusio-Ossola. Its principal river is the Toce, and its most important town Domodossola.
It is composed of one main valley (the Ossola proper) and seven side valleys: Anzasca, Antrona, Bognanco, Divedro, Antigorio, Formazza, Isorno and Vigezzo. It also includes parts of the Val Grande National Park, Italy’s largest wilderness area.
There are many etymological claims as to the origins of the name Ossola. The most likely is from the Celtic "hoch hill", which means "high lands". The German name for the valley is Eschental ("valley of the ash trees").