The Staffora is a river of the

Oltrepò Pavese The Oltrepò Pavese (; ; ) is a historical region making up the southern portion of the province of Pavia, in the northwest Italian region of Lombardy. The area is named after its location south of the Po (river), River Po as considered from th ...

in the

Province of Pavia The province of Pavia () is a Provinces of Italy, province in the Lombardy region of Italy. Its capital is Pavia. , the province has a population of 548,722 inhabitants and an area of ; the town of Pavia has a population of 72,205. History T ...

, north-west

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and a right-side tributary of the Po. It is probably the river known to the Romans as the Iria.

Course

The river rises in the Ligurian

Apennines The Apennines or Apennine Mountains ( ; or Ἀπέννινον ὄρος; or – a singular with plural meaning; )Latin ''Apenninus'' (Greek or ) has the form of an adjective, which would be segmented ''Apenn-inus'', often used with nouns s ...

at the Fontana di S. Giacomo, elevation , near the Passo del Giovà, which lies just to the east of the peak of Monte Chiappo in the commune of Santa Margherita di Staffora. It flows at first through a deep and narrow valley, receiving from the right the waters of the torrents Montagnola and Aronchio before reaching

Varzi Varzi is a ''comune'' (municipality) in the Province of Pavia in the Italian region Lombardy, located about 70 km south of Milan and about 40 km south of Pavia. It is one of I Borghi più belli d'Italia ("The most beautiful villages of I ...

where the valley begins to widen. The torrent Crenna enters from the right and the Lella from the left before the Staffora receives its major affluents: from the right: the torrent Nizza at Ponte Nizza and the torrent Ardivestra at Godiasco and from the left the torrent Semola near Ponte Nizza. The river flows through Salice Terme (administratively a

frazione A ''frazione'' (: ''frazioni'') is a type of subdivision of a ''comune'' ('municipality') in Italy, often a small village or hamlet outside the main town. Most ''frazioni'' were created during the Fascist era (1922–1943) as a way to consolidat ...

of Godiasco) before entering the Pianura Padana at Rivanazzano Terme. The Staffora then passes through the eastern outskirts of

Voghera image:Voghera Castle.jpg, The Castle of Voghera in a 19th-century etching. Voghera (Emilian dialect, Vogherese dialect of Emilian: ''Vughera''; Latin language, Latin: ''Forum Iulii Iriensium'') is a town and ''comune'' in the Province of Pavia i ...

, the principal town on its course, before entering the Po near Cervesina.

Regime

Although the river flows throughout the year, fed by perennial springs as well as by seasonal rains and melting ice, the regime is torrential: its discharge can vary between