Climbing K2: A Complete Guide to the Abruzzi Spur Route

The Abruzzi Spur Route Description

The most common climbing route that climbers take to ascend K2, the second highest mountain in the world, is the Abruzzi Spur or the Southeast Ridge. The ridge and the route loom menacingly above Base Camp on the Godwin-Austen Glacier on the south side of the mountain. The Abruzzi Spur route climbs steep snow and ice slopes broken by rock ribs and a couple of cliff bands that are surmounted with technical climbing.

K2’s Most Popular Route

About three-quarters of all the climbers who ascend K2 do so via the Abruzzi Spur. Moreover, most fatalities occur along its well-traveled ridge. The route is named after Italian climber Prince Luigi Amedeo, the Duke of Abruzzi, who led an expedition to K2 in 1909, making the first attempt on the ridge.

The Abruzzi Spur is Long

The route begins at the base of the ridge at 17,390 feet (5,300 meters) and ascends a staggering 10,862 feet (3,311 meters) to K2’s summit at 28,253 feet (8,612 meters). Consequently, the sheer length of the route, along with severe weather conditions and objective dangers, makes the Abruzzi Spur one of the most challenging and perilous routes among the world’s 8,000-meter peaks.

Major Topographic Features

Key topographical features on K2’s Abruzzi Spur include The House Chimney, The Black Pyramid, The Shoulder, and The Bottleneck. Each of these points presents its own set of technical difficulties and dangers. For instance, The Bottleneck, located below a 300-foot-high hanging ice cliff, is particularly hazardous as parts can break off, leading to potential avalanches that may kill or strand climbers above it, as evidenced by the tragic events of 2008.

Base Camp and Advanced Base Camp

Climbers establish Base Camp on the Godwin-Austen Glacier below K2’s great south wall. Subsequently, the Advanced Base Camp is typically relocated to the base of the Abruzzi Spur, approximately a mile further up the glacier. The route is methodically divided into camps situated at various elevations on the mountain.

The Abruzzi Spur: Camp 1 to The Shoulder

The House Chimney and Camp 2

From Camp 1, climbers proceed up mixed terrain consisting of snow and rock for 1,640 feet (500 meters) to Camp 2 located at 21,980 feet (6,700 meters). This camp is typically set against a cliff on a shoulder. Although it can be windy and cold, it remains relatively safe from avalanches. This segment features the renowned House Chimney, a 100-foot rock wall split by a chimney and crack system, rated 5.6 if free-climbed. Currently, the chimney is equipped with a network of old ropes, making it easier to ascend. The House Chimney received its name from American climber Bill House, who first climbed it in 1938.

The Black Pyramid

The striking Black Pyramid, a dark pyramid-shaped rock buttress, towers over Camp 2. This 1,200-foot section of the Abruzzi Spur presents some of the most technically challenging climbing along the entire route, with mixed rock and ice climbing on steep cliffs often covered in unstable snow slabs. While the technical rock climbing is less difficult than The House Chimney, its sustained steepness renders it serious and perilous. Climbers frequently fix ropes up the Black Pyramid to ease the ascent and descent.

Camp 3

After advancing 1,650 feet (500 meters) from Camp 2, climbers typically position Camp 3 at 24,100 feet (7,350 meters) above the Black Pyramid’s rocky wall and beneath steep, unstable snow slopes. The narrow valley between K2 and Broad Peak often acts as a wind funnel, channeling strong winds through the gap while rendering the snow slopes susceptible to avalanches from here to The Shoulder. Climbers generally stash extra gear, such as tents, sleeping bags, stoves, and food, on the Black Pyramid as they may need to retreat for supplies if Camp 3 succumbs to an avalanche.

Camp 4 and The Shoulder

From Camp 3, climbers quickly navigate steep snow slopes ranging from 25 to 40 degrees for 1,150 feet (342 meters) to the beginning of The Shoulder at 25,225 feet (7,689 meters). This segment is undertaken without fixed ropes. The Shoulder is a broad, low-angle bump on the ridge blanketed by ice and snow. There is no specific location for erecting Camp 4, the last established camp before the final push to the summit, as placement is influenced by weather conditions. Many climbers opt to position Camp 4 as high as possible, thereby reducing the elevation gain required on summit day. The camp typically ranges between 24,600 feet (7,500 meters) and 26,250 feet (8,000 meters).

The Abruzzi Spur: The Bottleneck and The Summit

Final Climbing Dangers

The summit, which is between 12 to 24 hours away depending on weather and a climber’s physical condition, stands approximately 2,100 vertical feet (650 meters) above Camp 4, which is situated on The Shoulder. Most climbers depart Camp 4 between 10 p.m. and 1 a.m. At this point, the aspiring K2 climber confronts the greatest alpine challenge, as the route up the Abruzzi Spur to the summit is fraught with perilous dangers that can claim a life in an instant. These hazards include extreme oxygen depletion at high altitude, unpredictable and frigid weather with strong winds and chilling temperatures, hard-packed snow and ice, and the threat of falling ice from a looming serac.

To the Summit

Following the lengthy ice traverse beneath the serac, the climbers ascend 300 feet up steep, wind-packed snow to the final summit ridge. This section, covered in ice, is not a place to linger due to its treacherous nature. Numerous climbers, including renowned British alpinist Alison Hargreaves and five companions in 1995, were tragically swept off this snow ridge by gale-force winds. Finally, there remains only a sharp snowy ridge that ascends 75 feet to the celebrated 28,253-foot (8,612-meter) summit of K2—the second highest point on Earth.

The Dangerous Descent

Congratulations, you have achieved the summit! Take a few photographs and smile for the camera, but do not linger. Daylight is running out, and there remains a considerable amount of difficult, hazardous climbing between the summit and Camp 4 below. Statistics show many accidents occur during the descent. Alarmingly, one in every seven climbers who reaches K2’s summit does not survive the descent. For those not using supplemental oxygen, the risk is one in five. Therefore, keep in mind: while the summit is a remarkable achievement, returning safely to Base Camp is mandatory.