Green Lake Trek
About
Green Lake is one of the most remote expedition treks in the Eastern Himalaya — a long, strenuous walk into the closed heart of North Sikkim to the edge of the Zemu Glacier, at the very base of Kanchenjunga. Following the route of early Kanchenjunga mountaineers from Lachen, it crosses pristine rhododendron forest, alpine meadow and glacial moraine to a basin above 16,000 ft.
What makes it special:
- A close-up base-camp view of Kanchenjunga, with Siniolchu, Simvo and Tent Peak ringing the valley
- The Zemu Glacier, one of the largest in the eastern Himalaya, on a genuinely off-grid trail
- True wilderness and solitude — this is a serious expedition, not a commercial day-trek
It's reserved for experienced, well-acclimatised trekkers; proper acclimatisation and a fit, prepared group are essential at this altitude.
Getting There
The trek begins at Lachen in North Sikkim, about 125 km and a 6–7 hour drive from Gangtok along the North Sikkim highway. Reach the region via NJP railway station or Bagdogra airport near Siliguri, then drive up to Gangtok and on to Lachen.
This is a restricted border zone: it needs a special trekking permit from the Sikkim Tourism Department after defence and Ministry of Home Affairs clearance — Indians require a Protected Area Permit (PAP) and foreign nationals a Restricted Area Permit (RAP), all arranged through registered Gangtok agencies well in advance. Build in an acclimatisation day at Lachen before heading higher.