The Iwokrama Forest is nearly of central Guyana located in the heart of the Guiana Shield, one of the four last pristine tropical forests in the world. It represents an important transition zone in rainfall, landforms, human histories and biological communities. At its widest, the area is, and the greatest extent in a north-south direction is 80 km. The Georgetown–Lethem Road dissects the forest, traversing about between the northeastern and southern boundaries. The forest lies between 4° and 5° north latitude and 58.5 and 59.5 degrees west longitude. The Iwokrama Forest is bordered to the west by the Pakaraima Mountains and to the east by the isolated highlands scattered through central-east Guyana, Suriname and French Guiana. It is also bordered by savannahs in the southwest and northeast of Guyana and southwestern Suriname. The Essequibo River forms the eastern boundary. The northern boundary is the Siparuni River. The Burro-Burro River runs through the centre, and most of its watershed is within the Forest. The area is covered with lowlandtropical forest, and dominated by tall tropical trees with a dense canopy 20 to 30 metres high. The Iwokrama Forest's ecosystem is located at the juncture of Amazonian and Guianan flora and fauna. As a result, it contains high species richness and several species of animals that are threatened or extinct across most of their former geographic ranges, like the giant anteater. The Iwokrama Forest has the highest species richness for fish and bats for any area this size in the world. It also has extraordinarily high bird diversity. Iwokrama Forest has also been identified as a global hotspot for several plant families, including Lecythidaceae and Chrysobalanaceae. At 1000 metres high, the Iwokrama Mountains form the geographic focal point of the Iwokrama Forest. They once provided a "place of refuge" for the Macushi people. The Iwokrama International Centre for Rain Forest Conservation and Development and the forest are named after this striking formation.