Major Rivers:

* Essequibo River: The largest river in Guyana and the third largest in South America. It flows for approximately 1,010 kilometers (628 miles) through the country, eventually emptying into the Atlantic Ocean.

* Demerara River: The second-largest river in Guyana, flowing for about 340 kilometers (211 miles). It flows through the country's heartland and is home to several important towns and cities.

* Berbice River: The third-largest river in Guyana, flowing for about 560 kilometers (348 miles). It is important for agriculture and fishing, and it also contains several important hydroelectric dams.

* Cuyuni River: A major tributary of the Essequibo River, it flows for about 720 kilometers (447 miles) through Guyana and Venezuela. It is known for its gold mining activity.

* Mazaruni River: Another major tributary of the Essequibo River, it flows for about 640 kilometers (398 miles). It is known for its scenic beauty and its potential for hydroelectric power.

Other Important Rivers:

* Potaro River: Known for its waterfalls, including the Kaieteur Falls, the tallest single-drop waterfall in the world.

* Rupununi River: A major river in the Rupununi Savanna, a vast region in southern Guyana.

* Corentyne River: Forms the boundary between Guyana and Suriname.

* Takutu River: Forms part of the border between Guyana and Brazil.

These rivers play a crucial role in Guyana's economy, transportation, and tourism. They also provide a habitat for diverse flora and fauna, making Guyana a biodiversity hotspot.