Siachen Glacier Deep Dive
Siachen is the longest glacier in the Karakoram and the second-longest non-polar glacier on Earth — roughly 76 km of mainstream ice, draining toward the Nubra valley in Indian Ladakh. For most of its history it was almost unvisited; since 1984 it has been the highest battlefield in the world, occupied by Indian and Pakistani troops at over 6,000 m. That military reality shapes everything about visiting and studying it.
Geography
Siachen runs roughly southeast from a complex of high passes on the Saltoro Ridge to a snout in the Nubra valley. Major tributaries include the Teram Shehr, Lolofond and Mamostong. The neighbouring Saltoro and Rimo systems share the same massif of seven-thousanders and eight-thousanders.
Discovery
The glacier was first explored systematically by the Workmans in 1911-12 — Fanny Bullock Workman and her husband mapped the tributaries and named several of the passes. K2 itself drains by way of the Godwin Austen Glacier, which connects to the Baltoro and ultimately to the Indus, not Siachen.
The Saltoro line
After the 1972 Shimla agreement, the line of control between India and Pakistan was not extended over the Saltoro ridge. In 1984 India launched Operation Meghdoot, occupying high posts along the ridge, and Pakistan responded with its own outposts further west. The two armies have held positions at altitude continuously since.
Climate and mass balance
The Karakoram has historically shown a more stable mass balance than the Himalaya — the "Karakoram anomaly." Recent studies, however, have detected accelerated thinning in the lower Siachen. Heavy winter snow continues but melt at lower elevations is increasing.
Visiting (civilians)
For civilians, only the lowest 4 km or so of Siachen can be visited, and only on Indian Army-led visits from Siachen Base Camp at Kumar. These trips are sporadic and limited; permits go through the Indian Army's Northern Command. No comparable access exists from the Pakistani side.
Scientific significance
The Siachen system holds among the largest reserves of ice in the Karakoram. Its meltwater feeds the Nubra River and ultimately the Indus. Because of access restrictions, ground-based monitoring is limited and most data comes from remote sensing.
Environmental concerns
The military occupation has had documented environmental costs — solid waste in the high camps, fuel spills, and accelerated melt attributed to soot deposition. Cleanup efforts have been intermittent on both sides.
Plan your next trip
The interactive map shows the published Saltoro line, the known base camp locations and the parts of Siachen that have ever been accessible to civilian visitors.