Nanda Devi Base Camp trek through Uttarakhand's Milam Valley is remote and challenging. Multi-day expedition reaching around 4,500 meters near India's second-highest peak. Long approach through ancient villages, glaciers, moraine fields. Needs experience, permits, and commitment. Best May-June, September-October. Raw wilderness few trekkers ever reach. Not for beginners. https://www.thinairexpedition.com/nanda-devi-base-camp-trek/