Baltoro Glacier: Trekking the River of Ice to K2
The Baltoro Glacier is a river of ice about 62 km long in Pakistan's central Karakoram, running from its snout near Paiju (about 3,400 m) up past Concordia (about 4,600 m), where the Godwin-Austen Glacier comes down from K2. Its meltwater becomes the Braldu River, which flows into the Shigar and then the Indus. The K2 Base Camp trek follows it for most of its length, past the Trango Towers, Masherbrum, Mitre Peak and the walls of the Gasherbrums. More than a third of its surface is covered in rock, so much of the walk is over stony moraine rather than white ice.
Facts and figures
- Length: about 62 km along its longest flowline, from glaciological surveys; other sources give 57–63 km.
- Area: about 524 km² of ice, in a drainage basin of about 1,500 km².
- Height: from its snout near Paiju at about 3,400 m to Concordia at about 4,600 m; its basin rises to the summit of K2.
- Tributaries: the Godwin-Austen Glacier from K2, the upper Baltoro and Abruzzi glaciers from Baltoro Kangri, and the Vigne Glacier from Chogolisa, on the Gondogoro La route, all meeting around Concordia.
- River: the Braldu, which joins the Shigar River and then the Indus at Skardu.
- Protection: the whole glacier lies inside Central Karakoram National Park.
The walk up the glacier
The trek starts where the jeep road ends, around Askole (about 3,000 m), and follows the Braldu to the snout of the glacier at Paiju (about 3,400 m), where many groups take a rest day. From there the trail climbs onto the ice: Khoburtse (about 3,900 m), Urdukas (about 4,000 m), Goro I and Goro II out on the ice (about 4,200 and 4,300–4,400 m), then Concordia (about 4,600 m). Beyond it lie Broad Peak Base Camp (about 4,800 m) and K2 Base Camp (about 5,000–5,150 m; published figures vary). Allow seven to nine days from Askole to K2 Base Camp, rest days included.
The Balti names are a guide to the land: Paiju means "salt" and Urdukas "split rock".
The mountains along the way
- Paiju Peak (6,610 m), above the snout, first climbed in 1976 by a Pakistani team.
- The Trango Towers (Great Trango, 6,286 m) and Uli Biaho, granite towers with some of the biggest cliffs on earth, on the north side.
- Masherbrum (7,821 m), the first peak the surveyors numbered, rising to the south from Paiju to Goro.
- The Muztagh Tower (about 7,275 m), on the north side of the middle glacier.
- Gasherbrum IV (7,925 m), whose west face, the Shining Wall, fills the head of the glacier for days.
- Mitre Peak (about 6,010 m), directly above the camp at Concordia.
- Chogolisa (7,665 m) and Baltoro Kangri (7,312 m), which Martin Conway named the Golden Throne in 1892.
A glacier under rock
The lower Baltoro hardly looks like ice. About 38% of its surface is covered with rock, from a few millimetres to more than a metre thick, and up to three metres near the snout; below about 5,000 m most of the glacier carries a debris layer. Trekkers walk over ridges of moraine, past meltwater streams and pools, with the ice showing mostly in crevasse walls and pinnacles. The glacier still moves under its rock, and like many Karakoram glaciers it hasn't shown the fast retreat seen across most of the Himalaya.
Who explored it
Adolf Schlagintweit reached the East Muztagh Pass from Askole in 1856, probably the first European in the area, and the same year Thomas Montgomerie's survey first measured K2 from far to the south. Henry Godwin-Austen surveyed the Baltoro region in 1861, though how far up the glacier he went is disputed. Martin Conway's expedition of 1892 mapped the upper glacier and named Concordia, the Golden Throne and the Godwin-Austen glacier. In 1909 the Duke of the Abruzzi's K2 expedition brought the photographer Vittorio Sella, whose pictures of the Baltoro are still widely regarded as among the finest mountain photographs ever taken.
Trekking the Baltoro
The Baltoro is a restricted zone: you need a trekking permit and a licensed guide, arranged through a registered operator, and the season runs from June to early September, with July and August the most settled. Our K2 Base Camp treks walk its full length to Concordia and K2 Base Camp in small groups, with porter crews from Askole and Hushe who know the glacier camp by camp.
Our small-group trek up the full length of the Baltoro to K2.
Open →Where the Baltoro meets the Godwin-Austen Glacier beneath K2.
Open →The granite cathedral of the middle Baltoro.
Open →Hidden Peak, Gasherbrum II and the Shining Wall at the glacier's head.
Open →Questions, answered
How long is the Baltoro Glacier?
About 62 km along its longest flowline, according to glaciological surveys; other sources give between 57 and 63 km, depending on where the measurement starts.
Where is the Baltoro Glacier?
In the central Karakoram in Gilgit-Baltistan, Pakistan, inside Central Karakoram National Park. It runs from near Paiju, a long day's walk above Askole, to Concordia below K2.
Is the Baltoro the longest glacier in the world?
No. It's among the longest glaciers outside the polar regions, but in the Karakoram alone the Siachen (about 70–76 km) and the Biafo (about 63–68 km) are longer.
Can you trek on the Baltoro Glacier?
Yes: the K2 Base Camp trek follows it for most of its length. It's a restricted zone, so you need a trekking permit and a licensed guide; the season runs from June to early September.