The four longest rivers are the Essequibo at 1,010 kilometres (628 mi) long, the Courantyne River at 724 kilometres (450 mi), the Berbice at 595 kilometres (370 mi), and the Demerara at 346 kilometres (215 mi).
The Corentyne river forms the border with Suriname.
Guyana is bordered by the Atlantic Ocean to the north, Brazil to the south and southwest, Suriname to the east and Venezuela to the west.
With 215,000 square kilometres (83,000 sq mi), Guyana is the fourth-smallest country on mainland South America after Uruguay, Suriname and French Guiana (an overseas region of France).
Guyana achieved independence from the United Kingdom on and became a republic on 23 February 1970, remaining a member of the Commonwealth.