Last updated
Country Italy
Physical characteristics
  location Ligurian Alps, on the slopes of Monte Saccarello
Po near Bassignana (AL)
Length276 km (171 mi)
Basin size8,234 km2 (3,179 sq mi)
  average123 m3/s (4,300 cu ft/s)

The Tanaro (Italian pronunciation:  [ˈtaːnaro] ), known as Tanarus in ancient times and Tane or Tani in piedmontese language, is a 276-kilometre (171 mi) long river in northwestern Italy. The river begins in the Ligurian Alps, near the border with France, and is the most significant right-side tributary to the Po in terms of length, size of drainage basin (partly Alpine, partly Apennine), and discharge.




The Tanaro proper begins in Liguria at the confluence of two small streams, the sources of which are in Piedmont: the Tanarello and the Negrone.

The main source of the Tanarello is on the slopes of Monte Saccarello above Monesi, a village belonging to the commune of Triora. This mountain straddles the French département of Alpes-Maritimes, the Piedmontese province of Cuneo and the Ligurian province of Imperia and marks the juncture of the watersheds between three drainage basins: that of the Tanaro itself; that of the Roya ( Italian Roia), which rises in France but enters the sea at Ventimiglia; and the Argentina, which flows into the Ligurian Sea at Taggia.

The sources of the Negrone are some 10 kilometres (6 mi) to the north, south of Punta Marguareis and very close to the French border.


The Tanaro flows past the towns Ceva, Alba, Asti, and Alessandria before entering the Po near Bassignana in the Province of Alessandria. At its confluence with Po, it is longer by about 50 kilometres (31 mi) than the upper Po, [1] a case similar to the famous Missouri tributary being longer than Mississippi in the United States.


The main tributaries to the Tanaro are the Stura di Demonte and the Borbore from the left and the Bormida and the Belbo from the right.


The flow is subject to a great deal of seasonal variation. Although the river has an Alpine origin, which is unique among the Po’s right-side tributaries, the Ligurian Alps are of an insufficient elevation and too close to the sea to allow for the formation of snow fields or glaciers large enough to provide a steady source of water during the summer. Furthermore, the Alpine zone forms only a part of the basin drained by the Tanaro. The seasonal regime of the river is therefore more typical of an Apennine stream, with a maximum discharge that can reach 1,700 cubic metres per second (60,000 cu ft/s), in spring and autumn and a very low rate of flow in the summer.

Flood events

1994 floods in Asti SWScan00028.tif
1994 floods in Asti

The river is highly prone to flooding. During the two hundred-year period between 1801 and 2001, sections of the Tanaro basin were affected by floods on 136 occasions, the most devastating being those in November 1994, when the whole of the river valley was affected by severe flooding, especially the town of Alessandria.


The left bank of the Tanaro River near Asti is the scene of the Battle of Pollentia on April 6, 402.

Related Research Articles

Piedmont Region of Italy

Piedmont is a region in northwest Italy, one of the 20 regions of the country. It borders the Liguria region to the south, the Lombardy and Emilia-Romagna regions to the east and the Aosta Valley region to the northwest; it also borders Switzerland to the northeast and France to the west. It has an area of 25,402 square kilometres (9,808 sq mi) and a population of 4,377,941 as of 30 November 2017. The capital of Piedmont is Turin.

Apennine Mountains Mountain range stretching 1000 km from the north to the south of Italy along its east coast, traversing the entire peninsula.

The Apennines or Apennine Mountains are a mountain range consisting of parallel smaller chains extending c. 1,200 km (750 mi) along the length of peninsular Italy. In the northwest they join with the Ligurian Alps at Altare. In the southwest they end at Reggio di Calabria, the coastal city at the tip of the peninsula. Since 2000 the Environment Ministry of Italy, following the recommendations of the Apennines Park of Europe Project, has been defining the Apennines System to include the mountains of north Sicily, for a total distance of 1,500 kilometres (930 mi). The system forms an arc enclosing the east side of the Ligurian and Tyrrhenian Seas.

Montferrat part of the region of Piedmont in Northern Italy

Montferrat is part of the region of Piedmont in Northern Italy. It comprises roughly the modern provinces of Alessandria and Asti. Montferrat is one of the most important wine districts of Italy. It also has a strong literary tradition, including the 18th century Asti-born poet and dramatist Vittorio Alfieri and the Alessandrian Umberto Eco.

Marengo (department) former French department in Italy (1802-1814)

Marengo[ma.ʁɛŋ.ɡo] was a department of the French Consulate and of the First French Empire in present-day Italy. It was named after the Marengo plain near Alessandria to commemorate the eponymous French victory. It was formed in 1802, when the Subalpine Republic was directly annexed to France. Its capital was Alessandria.

Stura di Demonte river in Italy

Stura di Demonte is a 115-kilometre (71 mi) long river in northwestern Italy (Piedmont).

Ligurian Alps mountain range in northwestern Italy

The Ligurian Alps are a mountain range in northwestern Italy. A small part is located in France. They form the south-western extremity of the Alps, separated from the Apennines by the Colle di Cadibona. The Col de Tende separates them from the Maritime Alps. They form the border between Piedmont in the north and Liguria in the south.

Dora Riparia river

The Dora Riparia is an alpine river, a left-hand tributary of the Po. It is 125 kilometres (78 mi) long, with a 1,231 square kilometres (475 sq mi) drainage basin. It originates in the Cottian Alps, close to the Col de Montgenèvre in France, where it is called the Piccola Dora. Its name becomes the Dora Riparia after the confluence with the Ripa in the Argentera Valley and the Thuras de Bousson close to Cesana.

Battle of Mondovì battle

The Battle of Mondovì was fought on 21 April 1796 between the French army of Napoleon Bonaparte and the army of the Kingdom of Sardinia-Piedmont led by Michelangelo Alessandro Colli-Marchi. The French victory meant that they had put the Ligurian Alps behind them, while the plains of Piedmont lay before them. A week later, King Victor Amadeus III sued for peace, taking his kingdom out of the First Coalition. The defeat of their Sardinian ally wrecked Austrian Habsburg strategy and led to the loss of northwest Italy to the First French Republic.

Ceva Comune in Piedmont, Italy

Ceva, the ancient Ceba, is a small Italian town in the province of Cuneo, region of Piedmont, 49 kilometres (30 mi) east of Cuneo. It lies on the right bank of the Tanaro on a wedge of land between that river and the Cevetta stream.

Ovada Comune in Piedmont, Italy

Ovada is a comune (municipality) of 11,484 inhabitants in the Province of Alessandria in the northern Italian region Piedmont, located about 90 kilometres (56 mi) southeast of Turin and about 30 kilometres (19 mi) south of Alessandria.

Belbo river in Italy

The Belbo is a river of southern Piedmont, Italy. It is a right-side tributary of the Tanaro.

Grana del Monferrato torrent stream

The Grana del Monferrato is a small Italian river, classified as a torrente, a right tributary of the Po, which runs almost entirely in the Province of Alessandria among the hills of the Basso Monferrato which lie between the Po to the north and the Tanaro to the south. Notwithstanding its modest flow, it is the most significant Po tributary of the Basso Monferrato in terms of its length, the extent of its drainage basin and its discharge.

The Statielli, Statiellātes, or Statiellenses were a small Ligurian tribe which inhabited an area south of the river Padus. Their chief town was Aquae Statiellae, on the road from Vada Sabatia, near Savona to Dertona (Tortona) and Placentia. The Statielli settled in the territory included to the west and north by the course of the Tanaro river, to the east by the Orba, and to the south by the Alpine-Apennine Ligurian watershed. Area now included between the current provinces of Alessandria, Savona, Asti and Cuneo.

Piemonte (wine) range of Italian wines made in the region of Piedmont

Piemonte wine is the range of Italian wines made in the region of Piedmont in the northwestern corner of Italy. The best-known wines from the region include Barolo and Barbaresco. They are made from the Nebbiolo grape. These wines are ideal for storage and a well-aged Barolo for instance may leave a feeling of drinking velvet because the tannins are polished and integrated more and more into the wine. As the wine matures the colour becomes more brownish and rust-red.

Piota river in Italy

The Piota is an Apennine torrent in the Province of Alessandria, north-west Italy.

Monte Saccarello mountain

Monte Saccarello (Italian) or Mont Saccarel (French) is a mountain located on the French-Italian border between Liguria, Piedmont and Provence-Alpes-Côte d'Azur.

Monte Tanarello

Monte Tanarello (Italian) or Mont Tanarel (French) is a 2094 metres high mountain located on the French-Italian border.

Passo Tanarello

Passo Tanarello or Pas du Tanarel at 2,042 m is a mountain pass in the Ligurian Alps. It connects the valleys of Roya in France and Tanaro in Italy.

Colle delle Selle Vecchie Mountain pass of the Ligurian Alps

Colle delle Selle Vecchie or Col de la Celle Vieille at 2,097 m is a mountain pass in the Ligurian Alps. It connects the valleys of Roya in France and Tanaro in Italy.

Colle dei Signori Mountain pass of the Ligurian Alps

The Colle dei Signori or Col des Seigneurs at 2,107 m is a mountain pass in the Ligurian Alps. It connects the valleys of Roya in France and Tanaro in Italy.



  1. "Tanaro Po, Italy". acquabuona.it. 2009. Retrieved 6 April 2009.

Coordinates: 45°00′20″N8°46′10″E / 45.00556°N 8.76944°E / 45.00556; 8.76944