Roughly 100km across two great glaciers joined at a vast snow basin — one of the longest ice traverses outside the polar regions.
The Biafo-Hispar traverse links the Biafo Glacier, flowing down toward Askole in Baltistan, with the Hispar Glacier, flowing down toward the Hispar valley in Nagar (Hunza). Together they form a continuous river of ice roughly 100km long, joined high up at Hispar La by Snow Lake (Lukpe Lawo) — a broad, almost level basin of snow and ice ringed by unnamed peaks. It is widely cited as one of the longest glacial systems outside the polar regions, and the crossing is among the most committing non-technical-but-serious treks anywhere in the Karakoram.
This is not a walk you ease into. You spend the better part of three weeks on moving ice, far from any road, village, or rescue. The reward is a kind of scale and silence that few landscapes on Earth can offer — a true high-altitude wilderness traverse rather than an out-and-back to a viewpoint.
| Typical direction | Askole (Baltistan) → Snow Lake → Hispar (Hunza/Nagar) |
| Total distance | ~100km of glacial traverse, point to point |
| Duration | ~20–22 days on the trek, plus travel days each end |
| High point | Hispar La, around 5,151m |
| Snow Lake | Lukpe Lawo basin, roughly 4,800–4,900m |
| Best months | July to early September |
| Difficulty | Serious; glacier travel, crevasse hazard, remote |
| Guide & porters | Essential — experienced glacier guide and porters required |
| Permits & costs | Snow Lake is a permit/operator-required zone; confirm current costs and permit requirements with a licensed operator |
In general terms, most parties start at Askole — the same roadhead used for the K2 Base Camp trek — and work up the Biafo Glacier over several days, gaining altitude steadily toward the snow line. The lower Biafo is rocky, morainal glacier; higher up it becomes a cleaner snow surface where roped travel becomes the norm.
The heart of the trek is Snow Lake, the great snow basin near Hispar La. From here the route crosses the pass and begins the long descent of the Hispar Glacier toward the village of Hispar in Nagar. Camps on the glacier are placed on stable ice or rock islands, and progress depends heavily on snow conditions, crevasse bridging, and weather.
Exact daily distances vary enormously with conditions and party strength, so treat any day-by-day plan as flexible. Build in spare days for weather and acclimatisation. Confirm current costs and permits with a local operator before committing.
Difficulty & acclimatisation: The combination of length, altitude, glacier travel, and remoteness makes this one of the harder treks in the region. Acclimatise properly before and during the approach, ascend gradually, and never push on with serious altitude symptoms — descent is the only cure, and rescue here is slow and uncertain.
Best season: The window is short — roughly mid-summer to early autumn, when the passes are crossable and weather is most settled. Earlier in the season means deeper, softer snow; later means colder nights and shortening days.
How to start: Most trekkers reach the Baltistan end via Skardu, then drive to Askole. Arrange your guide, porters, and logistics through a reputable outfitter — see our agencies directory. For the geography and culture of the valleys at either end, browse explore Gilgit-Baltistan, and compare with other treks such as Concordia. The peaks above the route connect to the wider Karakoram giants.
The traverse covers roughly 100km of glacier and usually takes about 20 to 22 days on the trek itself, plus travel days at each end. It is one of the longest glacial traverses outside the polar regions.
It is a serious, mountaineering-grade trek. You spend many days on moving ice, cross a pass over 5,000m, and travel through very remote terrain. Real fitness, prior altitude experience, and glacier-travel skills are needed.
Yes. An experienced glacier guide and a strong porter team are essential because of crevasse hazard, route-finding on snow, and the remoteness of the traverse. Arrange them through a reputable local operator.
The usual window is roughly July to early September, when the high pass is crossable and weather is most settled. Conditions vary year to year, so check current snow reports locally.
Snow Lake is a permit/operator-required zone, so you trek it with a licensed operator. Costs depend on group size, service level, and season, and requirements can change. Confirm current costs and permit needs directly with a licensed operator before you commit.