The Silent Valley National Park with an area of 237. 52 sq km is located in the Northeastern corner of Palakkad district. It rises abruptly to the Nilgiri Plateau in the North and overlooks the plains of Mannarkkad in the South. Extremely fragile, a unique preserve of tropical evergreen rain forests which is a veritable nursery of flora and fauna, some of which are found nowhere else in the world. The core of the Nilgiri Biosphere Reserve is the Silent Valley National Park. Despite its name, the Silent Valley (the clamour of Cicadas is conspicuously absent here) is a rich storehouse of biodiversity. It is a true Garden of Eden for students of life sciences, professional scientists and field biologists.