Overview of Cho La Pass

Cho La Pass (5,420 m) is the central crossing of the Khumbu Three Passes Trek - the glaciated col that links the Gokyo valley to the west with the Lobuche/Dzongla valley to the east. At 5,420 m, Cho La is the lowest of the three main passes (Renjo La is 5,360 m; Kongma La is 5,535 m) but is widely considered the most technically demanding: the eastern approach involves a short section of steep glaciated terrain (30 - 40°) where crampons and careful footwork are required.

For trekkers on the Three Passes circuit, Cho La is the crossing that most tests technical capability. The majority of trekkers complete it safely with good guiding and appropriate footwear - but it is not a standard walking pass and should not be treated as one. The combination of steep glaciated upper section, altitude-induced fatigue, and the need to cross before afternoon cloud builds makes Cho La one of the route-planning pivots of the Three Passes circuit.

Route Description

West to East (Gokyo → Dzongla, the standard direction):

From Gokyo (4,750 m), the approach crosses the lower Ngozumpa Glacier moraine southward to Thangnak (4,700 m) - 2 - 3 hours. From Thangnak, the route climbs the eastern valley wall to the glacier approach at approximately 5,000 m. The final 400 m to the pass summit crosses a glacier field that varies from firm snow to ice depending on season - this is the crampons section. The pass itself (5,420 m) is marked by prayer flags on a narrow rocky col between Cho Oyu's southern outliers and the unnamed peaks to the east.

The descent from the col to Dzongla (4,843 m) is steep loose scree for the first 100 m then a well-tracked rocky trail. Allow 6 - 8 hours total from Thangnak to Dzongla.

East to West (Dzongla → Thangnak): Less commonly trekked; the glacier approach is from the eastern side, which is easier (gentler angle) but requires careful navigation of the glacier surface. This direction is sometimes used by groups doing the Three Passes in reverse.

Difficulty and Technical Requirements

Cho La is graded moderate-technical. The specific requirements:

• Crampons: Required in most conditions October - May. The glacier section below the summit is 30 - 40° of ice or hard snow that is genuinely dangerous without crampons and dangerous technique with them. Rent crampons in Namche if not carrying your own; confirm they fit your boots properly before Gokyo.
• Trekking poles: Essential for the descent's loose scree section. Extended pole length for the downhill.
• Guide: Strongly recommended - the route across the glacier is not always obviously marked by cairns (which can be buried under snow), and route-finding errors on a glacier above 5,000 m in deteriorating weather have serious consequences.
• Altitude fitness: Having spent at least 2 nights at Gokyo (4,750 m) before attempting Cho La is strongly recommended. Attempting Cho La without adequate acclimatisation time adds significant physiological stress to the already demanding crossing.

Best Season and Conditions

The pass is susceptible to closure after significant snowfall at any time of year. Check conditions with teahouse owners in Gokyo the evening before attempting the crossing - local guides have current trail intelligence that changes daily in variable seasons.

Essential Tips for Cho La Pass

• Start early: Cross the glacier section before 11:00 when afternoon cloud and potential afternoon snow reduce visibility and increase ice melt instability. Depart Thangnak by 05:30 - 06:00.
• Do not attempt in poor visibility: The glacier surface above 5,200 m has crevasse zones. In cloud or fog, the route is not safely navigable without GPS and crevasse rescue equipment. Wait for clear weather.
• Bring a rope if guiding inexperienced trekkers: A 30 m rope allows your guide to belay trekkers on the steepest glaciated section. Most professional Khumbu guides carry a short rope for Cho La crossings.
• The crampons section is short: Approximately 200 - 300 m of glacier crossing - but those metres require full attention. Take your time; do not rush the crampon section regardless of group pressure or guide urgency.

Practical Information

• Altitude: 5,420 m (17,782 ft)
• Coordinates: 27.9411°N, 86.7473°E
• Type: Glaciated mountain pass
• Technical grade: Moderate-technical (crampons required)
• Best approached from: West (Gokyo side) - standard Three Passes direction
• Time from Thangnak to Dzongla: 6 - 8 hours
• Part of: Three Passes Trek (Renjo La, Cho La, Kongma La circuit)
• Best season: October - November; April - May