The Sinharaja Forest Reserve is a national park in Sri Lanka. The hilly virgin rain forest, part of the Sri Lanka lowland rain forest eco-region, was saved from the worst of commercial logging by its inaccessibility. It was designated a World Biosphere Reserve in 1978 and a World Heritage Site in 1988. The reserve's name translates as Kingdom of the Lions. The reserve is only 21 km from east to west, and a maximum of 7 km from north to south, but it is a treasure trove of endemic species, including trees, insects, amphibians, reptiles, birds and mammals. Because of the dense vegetation, wildlife is not as easily seen as at dry-zone national parks such as Yala. There are no elephants here and the fifteen or so leopards are rarely seen. The most common larger mammal is the endemic Purple-faced Langur. An interesting phenomenon is that birds tend to move in mixed feeding flocks, invariably led by the fearless Greater Racket-tailed Drongo and the noisy Orange-billed Babbler. Of Sri Lanka's 26 endemic birds, the 20 rain forest species all appear here, including the elusive Red-faced Malkoha, Green-billed Coucal and Sri Lanka Blue Magpie. Reptiles include the endemic Green Pit Viper and Hump-nosed Vipers, and there are a large variety of amphibians, especially tree frogs. Invertebrates include the endemic Common Birdwing Butterfly and the inevitable leeches.