It is located in the Province of Pordenone, with an orientation North-South and it is crossed by the River Meduna.
Three municipalities are present in the valley: Tramonti di Sopra, Tramonti di Sotto and Meduno, the latter being located where the River Meduna leaves the Alps and meets the plain.
Northward the valley borders on the Carnic Prealps, eastward on the Arzino and Cosa valleys, southward on the Cellina valley and South-West on the Colvera valley.
The territory has an altitude which ranges from 270 to 2300m a.s.l. The river network is represented by the basins of the River Arzino and River Meduna and by several streams: Chiarchia, Chiarzò, Comugna, Silisia, Tarcenò and Vielia.
The climate is intermediate between sub-continental and sub-mediterranean.
There are also several mountain peaks across the whole valley: Caserine Alte (m 2309) e Mount Dosàip (m 2062), Mount Fràscola (m 1961), Mount Valcalda (m 1908), Mount Rest (m 1780), Cuesta Spioléit (m 1687) and Col della Luna (m 1427).
Part of the municipality of Tramonti di Sopra falls within the Friulian Dolomites Natural Park. In the village of Tramonti di Sopra you can find the visitor center of the Park and the naturalistic museum.