Green Lake is, by most measures, the most demanding and remote trek in this entire guide — a two-week expedition into the restricted glacier terrain of North Sikkim, approaching Kanchenjunga’s eastern flank via the Zemu Glacier, one of the largest glaciers in the eastern Himalaya. Few trekking companies run it regularly, and fewer trekkers attempt it, which is precisely part of its appeal for those chasing genuinely untouched Himalayan terrain.
The route from Lachen follows the Zemu valley for days before reaching the glacier zone proper, with Green Lake itself serving as a base for exploring views toward Kanchenjunga and Siniolchu, a peak frequently ranked among the most beautiful in the world for its sheer, symmetrical faces.
Given the trek’s proximity to the India-China border, permits require significant advance planning through a registered operator, and the trek itself demands prior high-altitude expedition experience — this is not a route for anyone without a strong trekking résumé already behind them.
