Lhotse

May 18, 1956. Two Swiss climbers — Fritz Luchsinger and Ernst Reiss — step onto the summit of Lhotse for the first time. Earth's fourth-highest mountain. 8,516 metres. The air there contains 33% of the oxygen available at sea level. Three breaths to do the work of one. They'd shared a base camp with the Everest expedition of the same year — same logistics, same Khumbu Icefall, same ice wall. Two separate mountains joined at the shoulder.

The Tibetan name Lho Tse means "South Peak." It's accurate. Lhotse rises directly south of Everest, separated only by the South Col at 7,906 m. Together with Everest and Nuptse, it forms a massive horseshoe — one of the most vertical walls in the Himalayas. The South Face of Lhotse — 3,200 m of near-vertical relief — is still considered one of the hardest and most dangerous climbs on the planet, completed only a handful of times. The normal route is a different matter: it follows the Everest path to Camp 3, then diverges up the Reiss Couloir. Hard, not impossible. It spends 516 metres of elevation in the Death Zone.

Technical Overview

Route (Normal Route — Reiss Couloir)

Lhotse is climbed almost exclusively by the normal route, which shares the approach with the standard Everest route up to Camp 3. Access from Lukla (flight from Kathmandu), 8–10 days of trekking through the Khumbu region to Base Camp at 5,364 m.

Base Camp → Camp 1

5,364 m → 5,900 m | Elevation gain: +536 m | Time: 4–6h

The most objectively dangerous section. The Khumbu Icefall is a maze of shifting seracs — moving, groaning, unpredictable. Icefall doctors fix ropes and ladders each season. You go at night or very early morning, when cold temperatures slow (not stop) the movement. No two seasons look the same.

Camp 1 → Camp 2 (ABC)

5,900 m → 6,400 m | Elevation gain: +500 m | Time: 3–5h

The Western Cwm — the "Valley of Silence." A nearly flat glacial bowl, sun-drenched and wind-sheltered. Deceptive. On a calm afternoon, radiated heat from the glacier can push temperatures above 40°C. You walk early or you don't walk. Camp 2 (Advanced Base Camp) is where you'll spend most of your acclimatisation rotation time.

Camp 2 → Camp 3

6,400 m → 7,300 m | Elevation gain: +900 m | Time: 4–6h

The Lhotse Face. 900 metres of blue glacial ice at 40–50°, with sections pushing 80°. All fixed ropes. The rhythm becomes mechanical: jumar, step, breath. Jumar, step, breath. You're above 7,000 m now — the body is losing more than it's gaining. The Reiss Couloir begins to appear up to the right.

Camp 3 → Camp 4

7,300 m → ~7,900 m | Elevation gain: ~600 m | Time: 4–6h

The upper Lhotse Face. This is where the routes diverge: Everest climbers cut left toward the Geneva Spur and South Col; Lhotse climbers go straight up. Camp 4 sits on a small ledge at roughly 7,900 m — the last stop before the summit push.

Camp 4 → Summit

~7,900 m → 8,516 m | Elevation gain: ~616 m | Time: 5–8h

You leave at midnight or 1 a.m. The Reiss Couloir narrows as it rises — a channel of snow and ice at 45–55°, steeper in places. At this altitude, each step costs three or four breaths. The summit is a narrow point. Below it, the South Face drops 3 km almost vertically. To the north, Everest stands 333 metres higher. It looks close. It's a different mountain.

Oxygen & Acclimatisation

At 8,516 m, atmospheric pressure falls to around 333 hPa — one-third of sea level. The oxygen you're breathing is 33% of what you'd get at the coast. At those altitudes the body can't acclimatise: it deteriorates. Every hour above 8,000 m costs something that doesn't come back on the mountain.

Typical summit SpO₂ with supplemental oxygen: 50–65%. Without it, lower — with extreme risk of HACE (High Altitude Cerebral Edema) and HAPE (High Altitude Pulmonary Edema). Resting heart rate above 7,000 m commonly sits at 90–110 bpm.

Standard acclimatisation protocol:

1. BC → C1 → return: 1–2 days
2. BC → C2 → return: 1–2 days
3. Rest at BC: 5–7 days
4. Second rotation: BC → C3 → return: 1–2 days
5. Rest at BC: 5–7 days
6. Summit push: BC → C1 → C2 → C3 → C4 → Summit → C2 → BC

The full process takes 35–45 days. You can't compress it. Physiology works on weeks, not intentions.

Medical note: This information is educational and does not replace consultation with a high-altitude medicine specialist.

Preparation

Lhotse isn't an entry-level high-altitude objective. The technical demands of the Lhotse Face and Reiss Couloir — steep ice at altitudes where every movement is costly — require specific preparation. You'll need documented experience above 7,000 m, preferably with nights above 6,500 m on technical glacial terrain.

Minimum prerequisites: steep ice climbing (50–60°), confident jumar use on fixed ropes, autonomous movement on crevassed glacier, nights above 6,000 m. A technical Himalayan 7000er is the realistic minimum — Aconcagua alone doesn't prepare you for this.

Essential gear:

• Oxygen mask and regulator (Poisk or equivalent system)
• Oxygen bottles (3–5 × 4–6L for summit push)
• Expedition down suit rated to −45°C
• Double mountaineering boots for high altitude
• Technical 12-point crampons, rigid frame
• Technical ice axe, certified jumar, ice harness
• VHF radio, GPS, headlamp with spare batteries
• High-altitude medical kit (dexamethasone, nifedipine, acetazolamide)

Season: March–May is standard. The jet stream over the Himalayas tends to shift north in May, opening the weather windows that make summit attempts possible. Most teams target May 10–25. Autumn is rarely used for Lhotse.

Cost: commercial expeditions typically run $20,000–45,000 USD, covering Nepalese permits, Lukla logistics, Base Camp cook and porters, supplemental oxygen, and high-altitude Sherpa support.

Frequently Asked Questions

How much oxygen is there at Lhotse's summit?

At 8,516 m, Lhotse's summit has 33% of the oxygen available at sea level. Atmospheric pressure is approximately 333 hPa, compared to 1,013 hPa at sea level. Every breath delivers one-third the oxygen you'd get at the coast. Almost every climber uses supplemental oxygen above 7,000 m — without it, summit SpO₂ typically falls below 60%.

Is Lhotse harder than Everest?

On the normal route, Lhotse and Everest share the approach up to Camp 3. Above that, the Reiss Couloir is technically steeper than Everest's South Ridge — though shorter. Lhotse's normal route is rated AD/D, slightly harder than Everest's standard route (PD+/AD). The summit is 333 m lower, which reduces time in the Death Zone. Both are serious undertakings. Don't let the comparison make either one sound easy.

How many people have climbed Lhotse?

By late 2008, 371 climbers had reached the summit, with 20 fatalities. Numbers have grown since then with the expansion of commercial expeditions — but Lhotse remains one of the less-frequented 8,000ers, often overshadowed by its neighbour Everest.

Who made the first ascent of Lhotse?

Fritz Luchsinger and Ernst Reiss of Switzerland summited on May 18, 1956, as part of the joint Swiss Everest–Lhotse expedition. The first winter ascent came on December 31, 1988, by Polish climber Krzysztof Wielicki — a landmark in Himalayan winter mountaineering.

What's the best season to climb Lhotse?

March–May (pre-monsoon) is the standard window. The jet stream above the Himalayas typically shifts north in May, opening viable summit weather. Most expeditions target a summit date between May 10 and 25. Autumn (September–October) is theoretically possible but rarely used for this specific mountain.