The Staffora is a river of the

Oltrepò Pavese The Oltrepò Pavese (; lmo, label=Western Lombard, Ultrepò Paves) is an area of the Province of Pavia, in the north-west Italian region of Lombardy, which lies to the south of the river Po. It is ('beyond') the Po when considered from the p ...

in the

Province of Pavia The province of Pavia ( it, Provincia di Pavia) is a province in the region of Lombardy in northern 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. ...

, north-west

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

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

Romans Roman or Romans most often refers to: *Rome, the capital city of Italy * Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a lette ...

as the Iria.

Course

The river rises in the Ligurian Apennines 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 A commune is an alternative term for an intentional community. Commune or comună or comune or other derivations may also refer to: Administrative-territorial entities * Commune (administrative division), a municipality or township ** Communes of ...

Santa Margherita di Staffora Santa Margherita di Staffora is a ''comune'' (municipality) in the Province of Pavia in the Italian region Lombardy, located about 80 km south of Milan and about 50 km south of Pavia. As of 31 December 2004, it had a population of 589 and ...

. 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. Varzi borders the following municipalities: Bagnaria, Fabbrica Curone, G ...

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 Ponte Nizza is a ''comune'' (municipality) in the Province of Pavia in the Italian region Lombardy, located about 70 km south of Milan and about 35 km south of Pavia. Ponte Nizza borders the following municipalities: Bagnaria, Cecima, ...

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'' (plural: ) 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 consolidate territ ...

of Godiasco) before entering the

Pianura Padana The Po Valley, Po Plain, Plain of the Po, or Padan Plain ( it, Pianura Padana , or ''Val Padana'') is a major geographical feature of Northern Italy. It extends approximately in an east-west direction, with an area of including its Venetic ex ...

Rivanazzano Terme Rivanazzano Terme ( Lombard: ''La Riva''; known simply as ''Rivanazzano'' before 30 July 2009The name was officially changed by regional law 14.07.2009 no, 12, which followed a referendum held in Rivanazzano on 29 March 2009; the name of Rivanazzan ...

. The Staffora then passes through the eastern outskirts of

Voghera The Castle of Voghera in a 19th-century etching. Voghera ( Vogherese dialect of Emilian: ''Vughera''; Latin: ''Forum Iulii Iriensium'') is a town and ''comune'' in the Province of Pavia in the Italian region Lombardy. The population was 39,374 ...

, 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