Nouabalé-Ndoki National Park is a national park in the Republic of the Congo. Established in 1993, in the northern provinces of Congo, it is home to forest elephants, great apes, including western lowland gorillas and the eastern sub-species of chimpanzees and bongo. It is 3,921.61 km2 (1,514.14 sq mi) of pristine tropical rainforest with no human habitation within it and with human population densities in its periphery that are comparatively low for the sub-region. The forests have a rich biodiversity of 300 bird species, plus 1,000 plant and tree species which include endangered mahoganies.