Guyana has one of the largest unspoiled rainforests in South America, some parts of which are almost inaccessible by humans. The rich natural history of Guyana was described by early explorers Sir Walter Raleigh and Charles Waterton and later by naturalists Sir David Attenborough and Gerald Durrell. In 2008, the BBC broadcast a three-part programme called ''Lost Land of the Jaguar'' which highlighted the huge diversity of wildlife, including undiscovered species and rare species such as the giant otter and harpy eagle.