St. Lawrence River
  • Saint Lawrence River
  • French: Fleuve Saint-Laurent
Great Lakes Watershed/St. Lawrence
EtymologySaint Lawrence of Rome
CountryCanada, United States
ProvincesOntario, Quebec
StateNew York
TerritoriesAnishinaabewaki; Haudenosaunee Countries; Nitaskinan; Nionwentsïo [fr]; Nitassinan; Dawnland Countries
Physical characteristics
SourceLake Ontario
 • locationKingston, Ontario / Cape Vincent, New York
 • coordinates44°06′N 76°24′W / 44.100°N 76.400°W / 44.100; -76.400
 • elevation74.7 m (245 ft)
MouthGulf of St. Lawrence / Atlantic Ocean
 • location
Quebec, Canada
 • coordinates
49°30′N 64°30′W / 49.500°N 64.500°W / 49.500; -64.500
 • elevation
0 m (0 ft)
Length500 km (310 mi) excluding the estuary. C. 928 km if included.
Basin size1,344,200 km2 (519,000 sq mi)[1]
 • locationbelow the Saguenay River[2]
 • average16,800 m3/s (590,000 cu ft/s)[2]
 • locationQuebec City
 • average12,101 m3/s (427,300 cu ft/s)
 • locationMontreal
 • average10,000 m3/s (350,000 cu ft/s)
 • maximum17,000 m3/s (600,000 cu ft/s)
 • locationLake Ontario, Kingston
 • average7,410 m3/s (262,000 cu ft/s)

The St. Lawrence River (French: Fleuve Saint-Laurent [flœv sɛ̃lɔʁɑ̃]) is a large international river in the middle latitudes of North America connecting the Great Lakes to the North Atlantic Ocean. Its waters flow in a northeasterly direction from Lake Ontario to the Gulf of St. Lawrence, traversing Ontario and Quebec in Canada and New York in the United States. A section of the river demarcates the Canada–U.S. border.

As the primary drainage outflow of the Great Lakes Basin, the St. Lawrence has the second-highest discharge of any river in North America (after the Mississippi River) and the 16th-highest in the world. The estuary of St. Lawrence is often cited by scientists as the largest in the world. Significant natural landmarks of the river and estuary include the 1,864 river islands of the Thousand Islands, the endangered whales of Saguenay–St. Lawrence Marine Park, and the limestone monoliths of the Mingan Archipelago.

Long a transportation route to Indigenous peoples, the St. Lawrence River has played a key role in the history of Canada and in the development of cities such as Montreal and Quebec City. The river remains an important shipping route as the backbone of the St. Lawrence Seaway, a lock and canal system that enables world marine traffic to access the inland ports of the Great Lakes Waterway.


The river has been called a variety of names by local First Nations. Beginning in the 16th century, French explorers visited what is now Canada and gave the river names such as the Grand fleuve de Hochelaga and the Grande rivière du Canada,[3] where fleuve and rivière are two French words (fleuve being a river that flows into the sea).

The river's present name has been used since 1604 when it was recorded on a map by Samuel de Champlain[3] Champlain opted for the names Grande riviere de sainct Laurens and Fleuve sainct Laurens in his writings, supplanting the earlier names.[3] In contemporary French, the name is rendered as the fleuve Saint-Laurent. The name Saint-Laurent (Saint Lawrence) was originally applied to the eponymous bay by Jacques Cartier upon his arrival into the region on the 10th of August feast day for Saint Lawrence in 1535.[3]

Today, the river is still known by Indigenous nations by a number of distinct names. Innu-aimun, the language of Nitassinan, refers to it as Wepistukujaw Sipo/Wepìstùkwiyaht sīpu;[3][4] the Abenaki call it Moliantegok/Moliantekw ("Montréal River"),[3] Kchitegw/Ktsitekw/Gicitegw ("Great River"),[4] or Oss8genaizibo/Ws8genaisibo/Wsogenaisibo ("River of the Algonquins");[4] the Mohawk refer to it in Kanienʼkéha as Roiatatokenti, Raoteniateara,[3] Ken’tarókwen,[5] or Kaniatarowanénhne;[6] the Tuscarora call it Kahnawáˀkye or Kaniatarowanenneh ("Big Water Current");[7] the Algonquins (or Omàmiwininiwak) call it "the Walking Path" or Magtogoek[3][8] or Kitcikanii sipi, the "Large Water River";[4][9] the Huron-Wendats refer to it as Lada8anna or Laooendaooena;[4] and, the Atikamekw of Nitaskinan refer to it as Micta sipi ("Huge River").


Boats of the Transat Québec–Saint-Malo on the St. Lawrence River in 2000
Cross commemorating the one laid by Jacques-Cartier on October 7, 1535, Trois-Rivières
The Champlain Sea

With the draining of the Champlain Sea, due to a rebounding continent from the Last Glacial Maximum, the St. Lawrence River was formed. The Champlain Sea lasted from about 13,000 years ago to about 10,000 years ago and was continuously shrinking during that time, a process that continues today.[10][11] The head of the St. Lawrence River, near Lake Ontario, is home to the Thousand Islands.[12]

Today, the St. Lawrence River begins at the outflow of Lake Ontario and flows adjacent to Gananoque, Brockville, Morristown, Ogdensburg, Massena, Cornwall, Montreal, Trois-Rivières, and Quebec City before draining into the Gulf of St. Lawrence, often given as the largest estuary in the world.[13] The estuary begins at the eastern tip of Île d'Orléans, just downstream from Quebec City.[2] The river becomes tidal around Quebec City.[14]

The St. Lawrence River runs 3,058 kilometres (1,900 mi) from the farthest headwater to the mouth and 1,197 km (743.8 mi) from the outflow of Lake Ontario. These numbers include the estuary; without the estuary, the length from Lake Ontario is c. 500 km (c. 300 mi). The farthest headwater is the North River in the Mesabi Range at Hibbing, Minnesota. Its drainage area, which includes the Great Lakes, the world's largest system of freshwater lakes, is 1,344,200 square kilometres (518,998.5 sq mi), of which 839,200 km2 (324,016.9 sq mi) is in Canada and 505,000 km2 (194,981.6 sq mi) is in the United States. The basin covers parts of Ontario and Quebec in Canada, parts of Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, New York, Vermont, and nearly the entirety of the state of Michigan in the United States. The average discharge below the Saguenay River is 16,800 cubic metres per second (590,000 cu ft/s). At Quebec City, it is 12,101 m3/s (427,300 cu ft/s). The average discharge at the river's source, the outflow of Lake Ontario, is 7,410 m3/s (262,000 cu ft/s).[2]

The St. Lawrence River includes Lake Saint Francis at Salaberry-de-Valleyfield, Lake Saint-Louis south of Montreal and Lake Saint Pierre east of Montreal. It encompasses four archipelagoes: the Thousand Islands chain near Alexandria Bay, New York and Kingston, Ontario; the Hochelaga Archipelago, including the Island of Montreal and Île Jésus (Laval); the Lake St. Pierre Archipelago (classified a biosphere world reserve by the UNESCO in 2000)[15] and the smaller Mingan Archipelago. Other islands include Île d'Orléans near Quebec City and Anticosti Island north of the Gaspé. It is the second longest river in Canada.

Lake Champlain and the Ottawa, Richelieu, Saint-Maurice, Saint-François, Chaudière and Saguenay rivers drain into the St. Lawrence.

The St. Lawrence River is in a seismically active zone where fault reactivation is believed to occur along late Proterozoic to early Paleozoic normal faults related to the opening of the Iapetus Ocean. The faults in the area are rift-related and comprise the Saint Lawrence rift system.

According to the United States Geological Survey, the St. Lawrence Valley is a physiographic province of the larger Appalachian division, containing the Champlain section.[16] However, in Canada, where most of the valley is, it is instead considered part of a distinct St. Lawrence Lowlands physiographic division, and not part of the Appalachian division at all.[17]


Map of 1543 showing Cartier's discoveries
Basque settlements and sites dating from the 16th and 17th centuries
The St. Lawrence River with land depicted on both sides. There is a canoe and a boat on the river and birds flying over the river.
Watercolour (c. 1792) by Elizabeth Simcoe depicting a bend in the St. Lawrence River in Quebec

First Nations

Flowing through and adjacent to numerous Indigenous homelands, the large river was always and remains to this day a primary thoroughfare for many peoples. Beginning in Dawnland at the Gulf of St. Lawrence, the river borders Mi'kma'ki[18] in the South (what is today known as the Canadian Maritimes), and Nitassinan in the North, the national territory of the Innu people.[19] On the south shore beyond the Mi'kmaw district of Gespe'gewa'ki,[18] the river passes Wolastokuk (the Maliseet homeland), Pαnawαhpskewahki (the Penobscot homeland), and Ndakinna (the Abenaki homeland).[20] Continuing, the river passes through the former country of the St. Lawrence Iroquois and then three of the six homelands of the Haudenosaunee: the Mohawk or Kanienʼkehá꞉ka, the Oneida or Onyota'a:ka, and the Onondaga or Onöñda’gaga’.[20]

In the early 17th century, the Huron-Wendat Nation migrated from their original country of Huronia to what is now known as Nionwentsïo centred around Wendake.[21][22] Nionwentsïo occupies both the north and south shores of the river,[21] overlapping with Nitassinan and the more western Wabanaki or Dawnland countries.[20] Adjacent on the north shore is the Atikamekw territorial homeland of Nitaskinan[23][24] and, upstream, the further reaches of Anishinaabewaki, specifically the homelands of the Algonquin and Mississauga Nations.[20]

European exploration

The Norse explored the Gulf of St. Lawrence in the 11th century and were followed by fifteenth- and early sixteenth-century European mariners, such as John Cabot, and the brothers Gaspar and Miguel Corte-Real. The first European explorer known to have sailed up the St. Lawrence River itself was Jacques Cartier. At that time, the land along the river described as "about two leagues, a mountain as tall as a heap of wheat" was inhabited by the St. Lawrence Iroquoians. During Cartier's second voyage in 1535, because Cartier arrived in the estuary on Saint Lawrence's feast day 10 August, he named it the Gulf of Saint Lawrence.[25] [26]

The St. Lawrence River is today partly within the U.S. and as such is that country's sixth oldest surviving European place-name.[27]

Early colonists

The earliest regular Europeans in the area were the Basques, who came to the St Lawrence Gulf and River in pursuit of whales from the early 16th century. The Basque whalers and fishermen traded with indigenous Americans and set up settlements, leaving vestiges all over the coast of eastern Canada and deep into the St. Lawrence River. Basque commercial and fishing activity reached its peak before the Armada Invencible's disaster (1588), when the Basque whaling fleet was confiscated by King Philip II of Spain. Initially, the whaling galleons from Labourd were not affected by the Spanish defeat.

Until the early 17th century, the French used the name Rivière du Canada to designate the St. Lawrence upstream to Montreal and the Ottawa River after Montreal. The St. Lawrence River served as the main route for European exploration of the North American interior, first pioneered by French explorer Samuel de Champlain.

Colonial control

Control of the river was crucial to British strategy to capture New France in the Seven Years' War. Having captured Louisbourg in 1758, the British sailed up to Quebec the following year thanks to charts drawn up by James Cook. British troops were ferried via the St. Lawrence to attack the city from the west, which they successfully did at the Battle of the Plains of Abraham. The river was used again by the British to defeat the French siege of Quebec under the Chevalier de Lévis in 1760.

In 1809, the first steamboat to ply its trade on the St. Lawrence was built and operated by John Molson and associates, a scant two years after Fulton's steam-powered navigation of the Hudson River. The Accommodation with ten passengers made her maiden voyage from Montreal to Quebec City in 66 hours, for 30 of which she was at anchor. She had a keel of 75 feet, and a length overall of 85 feet. The cost of a ticket was eight dollars upstream, and nine dollars down. She had berths that year for twenty passengers.[28] Within a decade, daily service was available in the hotly-contested Montreal-Quebec route.[29]

Because of the virtually impassable Lachine Rapids, the St. Lawrence was once continuously navigable only as far as Montreal. Opened in 1825, the Lachine Canal was the first to allow ships to pass the rapids. An extensive system of canals and locks, known as the St. Lawrence Seaway, was officially opened on 26 June 1959 by Elizabeth II (representing Canada) and President Dwight D. Eisenhower (representing the United States). The Seaway (including the Welland Canal) now permits ocean-going vessels to pass all the way to Lake Superior.

Modern Canada

During the Second World War, the Battle of the St. Lawrence involved submarine and anti-submarine actions throughout the lower St. Lawrence River and the entire Gulf of St. Lawrence, Strait of Belle Isle and Cabot Strait from May to October 1942, September 1943, and again in October and November 1944. During this time, German U-boats sank several merchant marine ships and three Canadian warships.

In the late 1970s, the river was the subject of a successful ecological campaign (called "Save the River"), originally responding to planned development by the United States Army Corps of Engineers. The campaign was organized, among others, by Abbie Hoffman.[30]

Resident whales

See also: Saguenay–St. Lawrence Marine Park

Watching fin whales off Tadoussac


The source of the North River in the Mesabi Range in Minnesota (Seven Beaver Lake) is considered to be the source of the St. Lawrence River. Because it crosses so many lakes, the water system frequently changes its name. From source to mouth, the names are:

The St. Lawrence River also passes through Lake Saint-Louis and Lake Saint-Pierre in Quebec.

Looking North East where the St. Lawrence River narrows, between Quebec City (left foreground) and Lévis (seen at right). The Île d'Orléans appears in the central distance.


The St. Lawrence River is at the heart of many Quebec novels (Anne Hébert's Kamouraska, Réjean Ducharme's L'avalée des avalés), poems (in works of Pierre Morency, Bernard Pozier), and songs (Leonard Cohen's "Suzanne", Michel Rivard's "L'oubli", Joe Dassin's "Dans les yeux d'Émilie", and André Gagnon's "Le Saint-Laurent"). The river was the setting for the Canadian television drama series Seaway. The river has also been portrayed in paintings, notably by the Group of Seven. In addition, the river is the namesake of Saint-Laurent Herald at the Canadian Heraldic Authority.

In 1980 Jacques Cousteau traveled to Canada to make two films on the St. Lawrence River and the Great Lakes, Cries from the Deep and St. Lawrence: Stairway to the Sea.[39]

A Canadian animated short film, directed by Frédéric Back, The Mighty River (French: Le Fleuve aux grandes eaux) was released in 1993. It won a number of awards in America, Asia, and Europe, and was nominated for an Academy Award for Best Animated Short Film.

Musician David Usher released the song "St. Lawrence River" on his Little Songs album in 1998.[40]

The novel and film Black Robe are set primarily on the St. Lawrence River during the 17th century.

See also


  1. ^ "Rivers". Atlas of Canada. Natural Resources Canada. Archived from the original on 22 January 2013.
  2. ^ a b c d Benke, Arthur C.; Cushing, Colbert E. (2005). Rivers of North America. Academic Press. pp. 989–990. ISBN 978-0-12-088253-3.
  3. ^ a b c d e f g h "Fleuve Saint-Laurent". Commission de toponymie Québec. Gouvernement du Québec. Retrieved 28 December 2021.
  4. ^ a b c d e Lozier, Jean-François (2018). Flesh Reborn: The Saint Lawrence Valley Mission Settlements through the Seventeenth Century. Montréal: McGill-Queens University Press. p. 306. ISBN 9780773553989. Retrieved 28 December 2021.
  5. ^ Doolittle, Benjamin (25 August 2016). "St. Lawrence (Upper river)". Kanienʼkéha Dictionary. Retrieved 28 December 2021.
  6. ^ Doolittle, Benjamin (25 August 2016). "St. Lawrence, USA & CA". Kanienʼkéha Dictionary. Retrieved 28 December 2021.
  7. ^ Rudes, B. Tuscarora English Dictionary Toronto: University of Toronto Press, 1999
  8. ^ Toussaint, Jean-Patrick. "Il était une fois un fleuve... et nous". Agence Science-Presse (in French). Retrieved 28 December 2021.
  9. ^ Cuoq, Jean André (1886). Lexique de la langue algonquine (in French). Montréal: J. Chapleau. Retrieved 28 December 2021.
  10. ^ Lake Champlain Basin Atlas: Geology Page Archived 20 July 2008 at the Wayback Machine
  11. ^ Miller, William J. (2015). Geology: The Science of the Earth's Crust (Illustrations). P. F. Collier & Son Company. p. 37. GGKEY:Y3TD08H3RAT.
  12. ^ "St. Lawrence River Ecosystem". Save The River! Thousand Islands - Clayton NY on the St. Lawrence River. Retrieved 9 February 2023.
  13. ^ "Estuary - National Geographic Society". Retrieved 16 August 2022.
  14. ^ Dawson, Samuel Edward (October 2007). The Saint Lawrence: Its Basin and Border-lands. Heritage Books. p. 36. ISBN 978-0-7884-2252-2. Retrieved 21 March 2011.
  15. ^ Lac Saint-Pierre et son archipel Archived 2 April 2015 at the Wayback Machine. (2008-11-07). Retrieved 2013-07-12.
  16. ^ "Physiographic divisions of the conterminous U.S." U.S. Geological Survey. Retrieved 6 December 2007.
  17. ^ "Physiographic Regions of Canada" (PDF). Natural Resources Canada. Natural Resources Canada. Archived (PDF) from the original on 21 October 2017. Retrieved 18 February 2017.
  18. ^ a b "Gespe'gewa'gi : Our District Territory". Mi’gmawei Mawiomi Secretariat. Mi’gmawei Mawio’mi. Retrieved 28 December 2021.
  19. ^ Nitassinan: The Innu Struggle to Reclaim Their Homeland, Douglas & McIntyre, December 1991, 240pp, by Marie Wadden, ISBN 978-1-55365-731-6, (book link) Archived 2013-01-21 at
  20. ^ a b c d "Territories". Retrieved 28 December 2021.
  21. ^ a b "Carte du Nionwentsïo". Nation Huron-Wendat. Nation Huronne-Wendat. Retrieved 28 December 2021.
  22. ^ Jaenen, Cornelius J. "Murray Treaty of Longueuil (1760)". The Canadian Encyclopedia. Historica Canada. Retrieved 28 December 2021.
  23. ^ "Les Attikameks s'attaquent à l'indifférence de Québec". Le Devoir (in French). 9 September 2014. Retrieved 20 April 2017.
  24. ^ "Les Atikamekw déclarent leur souveraineté". (in French). 8 September 2014. Retrieved 20 April 2017.
  25. ^ Johnson, William Henry (20 May 2007). French Pathfinders in North America. Retrieved 27 February 2011 – via Project Gutenberg.
  26. ^ Bideaux, Michel (1986). Jacques Cartier: Relations (in French). Les Presses de l'Université de Montréal. pp. 130–131. Retrieved 20 November 2021 – via Bibliothèque et Archives nationales du Québec.
  27. ^ The Spanish names Florida, Dry Tortugas, Cape Canaveral, Appalachian, and California appeared earlier.....From Spanish historian Antonio de Herrera y Tordesillas's accounts, published in 1601 -- Stewart, George (1945). Names on the Land: A Historical Account of Place-Naming in the United States. New York: Random House. pp. 11–17, 29.
  28. ^ Denison 1955, p. 65
  29. ^ Denison 1955, p. 91
  30. ^ "Save the River!". 1 November 2008. Archived from the original on 1 November 2008. Retrieved 27 May 2019.
  31. ^ "Une baleine noire en vue! Merci d'appeler Urgences Mammifères Marins! - Baleines en direct". 12 July 2013.
  32. ^ "Introduction". Archived from the original on 22 October 2013. Retrieved 5 February 2016.
  33. ^ "Hear them coming: right whales return to the Gulf of St. Lawrence". Fisheries and Oceans Canada Homepage. 22 April 2013. Retrieved 5 February 2016.
  34. ^ "Une baleine noire dans le Parc marin du Saguenay-Saint-Laurent".
  35. ^ "Une baleine noire observée près de l'île Rouge - Baleines en direct". 10 July 2015.
  36. ^ "Regional Species Extinctions - Examples of regional species extinctions over the last 1000 years and more" (PDF). Archived from the original (PDF) on 25 April 2011.
  37. ^ "Saint Lawrence River and Seaway". Encyclopædia Britannica. Retrieved 7 September 2009.
  38. ^ "Saint Lawrence". MSN Encarta. Archived from the original on 6 July 2008. Retrieved 7 September 2009.
  39. ^ Ohayon, Albert (2009). "When Cousteau Came to Canada". National Film Board of Canada. Retrieved 25 October 2009.
  40. ^ "Little Songs: David Usher: Music".