The Sikkim-Bengal Himalaya is a unique section of the entire Himalayan mountain system. It shows various types of stratigraphic and geomorphic features within very small areal extent including the largest massif of Kangchendzonga-innumerable lofty spires rising on stout Ranges- very deep rooted Thrusts- Nappes and Transcurrent Fault (Lachen valley)- large Tectonic window (Namchi area)- and also different types of landforms produced by glacial-glacio-fluvial-periglacial and fluvial processes.