The Khangchendzonga National Park, now named as Biosphere reserve in Sikkim may be aptly called the haven of prized Musk Deer, elusive Snow Leopard and the shy Himalayan Tahr, the Shapi of Sikkim. The National Park occupies a place at the apex amongst the high altitude National Parks in the country and is endowed with one of the most magnificent high altitude ecosystems in the world.
This park which also came into existence through the generosity of heart and purse of idealists who having realised the beauties and ecstasy of the region, is probably the largest biologically intact continuous tract of mountainous land with valleys of lush green forests, meadows, alpine lands reserved primarily for the conservation of its native wildlife.
The trek routes from Yuksom are : Bakim - Dzongri - Thangshing - Samuteng - Goechala Dzongri Base Camp - Rathong - Khangerteng Thangshing - Lam Pokhari - Kasturi Orar - Lapdong - Tashiding (Road Head). These places in the Khangchendzonga National Park are generally included in their itineraries in West Sikkim.
The traditional route of mountaineers is Lucanes Jakchen-Yabuk-Rest Camp (Marco Polo Camp) - Green Lake . Another detour traverse but murderous route is Lachen-Thasngu (13,695') Muguthang (16,000') - Thay La (17,000') - Khyoksa La (18,000') Rest Camp-Green Lake. Green 1,ake area is again is again developing into a take off point for mountaineering expeditions to the peaks of the surrounding area.
Areas beyond Chungthang towards Lachen, Green Lake are prohibited areas. Foreign nationals would require a restricted area permit from the Ministry of Home Affairs. Government of India, Delhi to visit areas in this part of the region.