The Courantyne River is a river in northern South America in Suriname and Guyana. It is the longest river in the country and creates the border between Suriname and the East Berbice-Corentyne region of Guyana.

Suriname, officially the Republic of Suriname, is a country in northern South America, sometimes considered part of the Caribbean and the West Indies. Situated slightly north of the equator, over 90% of its territory is covered by rainforests, the highest proportion of forest cover in the world. Suriname is bordered by the Atlantic Ocean to the north, French Guiana to the east, Guyana to the west, and Brazil to the south. It is the smallest country in South America by both population and territory, with around 612,985 inhabitants in an area of approximately 163,820 square kilometers. The capital and largest city is Paramaribo, which is home to roughly half the population.