le Canal latéral à la Garonne

The Garonne lateral canal

Le Canal latéral à la Garonne

With the Midi canal, the lateral canal of the Garonne forms the second part of the grand waterway commonly named the canal of the Two Seas. It is the prolongation leading to the Atlantic Ocean.

Navigation on the Garonne lateral canal starts at Toulouse and ends at Castets et Castillon.

Construction began in 1838 and ended in 1856.

The Garonne lateral canal is 193.00 kilometres long (119.92 miles) with a total of 193.00 kilometres of navigable waterway.

There is a total of 53 locks, with an average of 1 lock every 3.64 kilometres (2.26 miles).

The highest altitude of the Garonne lateral canal is 132.00 metres (433′ 1″ ft) above sea level.

From Toulouse to Castets et Castillon

The water draft is 1.60 metres (5′ 3″ ft) and the air draft is 3.60 metres (11′ 10″ ft).

General lock size

There are "Freycinet" lock types.
Lock length 39.00 metres (127′ 11″ ft)
Lock width 6.00 metres (19′ 8″ ft)

5 Montech locks

There are "Small" lock types.
Lock length 28.50 metres (93′ 6″ ft)
Lock width 6.00 metres (19′ 8″ ft)

Features and structures to discover

Pont-canal d'Agen

The canal bridge is 539 metres long and 10 metres above the river Garonne. Construction finished in 1847 but service started in 1849.


Geographical positions from ///teach.writers.abolish to ///risking.restored.atoms

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Barges cruising on the Garonne lateral canal

Name Itinerary Passengers
Rosa Gascony: Montauban to Boé 8 View the itinerary
Rosa Bordeaux: Castets-en-Dorthe to Boé 8 View the itinerary

Self-drive boats cruising on the Garonne lateral canal

Fleet Cruise route
Locaboat Aquitaine View the Locaboat boats
Nicols Aquitaine View the Nicols boats
Locaboat The Midi & the Camargue View the Locaboat boats

The Midi canal connects the city of Toulouse to the Mediterranean Sea at Sète. Its completion in 1681 inaugurated the first major step in the dream project of linking the Atlantic to the Mediterranean. The Marquis de Vauban, who undertook important changes and modifications to the Midi canal soon after it was finished, had plans to dig a lateral canal to the Garonne. The absence of waterways on the same scale as the Midi canal had serious economic consequences on the lower Garonne basin. Navigating from Toulouse to Bordeaux took around 8 days, and up to 15 were needed for the return journey. Several projects were submitted to authorities during the 18thcentury but they were deemed unfeasible. It took 150 years to start the construction of the lateral canal that would allow getting around the tricky and intermittently unnavigable Garonne.

In 1838, the construction of the canal began under the oversight of engineer Jean-Baptiste de Baudre who had previous experience in developing ports and rivers across the country. With its several branches, the Garonne canal is 213 kilometres long. Like the Midi canal, it was a long and difficult work to build for both political and technical reasons. The different sections of the canal were incrementally completed, and the canal was finished and inaugurated in 1856; six years after de Baudre’s death who, like Riquet, never saw the end of his work. The canal proved to be a financial burden and, in 1852, it was conceded to the Midi Railway Company which financed the last segment between the Baïse river mouth and Castets-en-Dorthe. As railroad transportation was then constantly increasing, the company had the ploy to lower freight on the canal, which, although completed, greatly suffered from trains.

The lateral canal of the Garonne went through a similar pattern to the other Midi waterways. Freight and navigation diminished drastically during the 20th century. The reasons were the competition of railroads and roads and ageing infrastructure. Modernization was acted in the1970s and locks were refitted to the Freycinet gauge. A highlight of this transformation was the creation of the Montech water slope allowing 40-metre-long boats to bypass five locks.

With other nearby waterways such as the Baïse, Dordogne and Garonne rivers, the lateral canal of the Garonne is a perfect gateway to enjoy the Nouvelle-Aquitaine and Occitanie regions. Restaurants and traditional open-air markets to sample regional cuisine on board or in the many beautiful cities are plenty. There are many famous wines like St. Emilion or Margaux, and delicacies like duck confit or truffles. At Agen, you will discover several of the city’s ancient towers, and a covered market, before crossing the Garonne river on the 500-metre-long water bridge. Strolling a few kilometres away from the canal will be an amazing occasion to visit beautiful towns and villages filled with history and architectural wonders like in fortified La Réole built around an old priory.


  • Brunet, Roger (1959), « Le trafic des canaux du Midi » in Revue géographique des Pyrénées et du Sud-Ouest, n°30, pp. 179-188.
  • (s.d.), « Le canal latéral à la Garonne » in Projet Babel [Online].
  • Marconis, Robert (1981), « Les canaux du Midi. Outil économique ou monument du patrimoine régional » in Revue géographique des Pyrénées et du Sud-Ouest, n°52, pp. 7-40.
  • Zannese, Françoise (2014), « De la Garonne au Canal de Garonne. Le barrage de Beauregard » in Découvertes de l’Aquitaine-Région Aquitaine [Online] .

More details about The Aquitaine & Bordeaux region