Virunga National Park is a UNESCO World Heritage Site in the eastern Democratic Republic of Congo, on the border of Uganda and Rwanda. Virunga is Africa’s oldest national park and is also the continent’s most biologically diverse protected area. The park’s 7800 square kilometers (3000 square miles) includes forests, savannas, lava plains, swamps, erosion valleys, active volcanoes, and the glaciated peaks of the Rwenzori mountains. Virunga is home to about a quarter of the world’s critically endangered mountain gorillas. The park’s two other Great Ape species, eastern lowland Grauer’s gorillas and chimpanzees, make Virunga the only park in the world to host three taxa of Great Apes. Another prominent inhabitant of the park is the Okapi, an endangered species that resembles a zebra but is more closely related to the giraffe. Large colonies of hippopotami, forest and savanna elephants, lions, and numerous rare bird species can also be found in the park.