The Essequibo River (Spanish: Río Esequibo) is the largest river in Guyana, and the largest river between the Orinoco and Amazon. Rising in the Acarai Mountains near the Brazil-Guyana border, the Essequibo flows to the north for 1,010 kilometres (630 mi) through forest and savanna into the Atlantic Ocean.
The river runs through the Guianan moist forests ecoregion. There are countless rapids and waterfalls (e. g., Kaieteur Falls on the Potaro river) along the route of the Essequibo, and its 20-kilometre (12 mi) wide estuary is dotted with numerous small islands. It enters the Atlantic 21 kilometres (13 mi) from Georgetown, the capital city of Guyana. The river features Murrays Fall, Pot Falls, and Kumaka Falls.
Its many tributaries include the Rupununi, Potaro, Mazaruni, Siparuni, Kiyuwini, Konawaruk and Cuyuni rivers. For over 30 kilometres (19 mi) from its mouth, the river's channel is divided by the large flat and fertile islands of Leguan, about 28 square kilometres (11 sq mi), Wakenaam, about 44 square kilometres (17 sq mi), and Hog Island, about 60 square kilometres (23 sq mi). Fort Island is off the eastern side of Hog Island. Fort Island was the seat of government of the country during the Dutch colonial era.