silent valley:

The core of the Nilgiri biosphere reserve, the Silent Valley national park is probably one of the most magnificent gifts of nature to mankind, a unique preserve of tropical rain forests in all its pristine glory with an almost unbroken ecological history. Thanks to its difficult terrain and remoteness, the extent of degradation is minimal in comparison with other sanctuaries.

The Silent Valley forest ranges in elevation from 900 to 2500 m above mean sea level and gets an average rainfall of 3000 to 6000 mm per year. Silent Valley is well known for tropical wet evergreen forests (rain forests) that harbor rare plants and animals. Unlike in most other sanctuaries, viewing wild animals in this park is quite difficult because of the thick vegetation