Most people who struggle on the Circuit do so because they climbed too quickly between about 3,500 m and 4,500 m. This page describes a safe profile with approximate sleeping altitudes. It is general guidance, not medical advice. See our broader page on altitude on Annapurna treks too.
The principle
Altitude illness depends on how fast you go up, not how fit you are. A reliable rule is to limit the gain in sleeping altitude above 3,000 m to roughly 300 to 500 m per night, and to add a rest day every 1,000 m. This pace is slower than the way many people trek, which is why they get into trouble.
A sample profile
Figures are approximate, and small differences between maps and your own watch are normal.
- Night 1 to 5: Besisahar to Dharapani area, about 760 m to 1,960 m. No altitude concern.
- Night 6: Chame, about 2,710 m.
- Night 7: Pisang, about 3,200 m.
- Night 8 and 9: Manang, about 3,540 m, with a rest day in between.
- Night 10: Yak Kharka, about 4,000 m.
- Night 11: Thorong Phedi, about 4,450 m, or High Camp, about 4,880 m.
- Night 12: Muktinath, about 3,710 m, after the pass.
The jump from Manang to Thorong Phedi is about 900 m over two nights, which is acceptable when you take the pace seriously.
The Manang rest day
The Manang rest day is the most important of the whole trek. Use it for a climb-high-sleep-low hike, such as to the Gangapurna lake viewpoint or higher toward Ice Lake or Praken Gompa, and return to sleep in Manang. The Himalayan Rescue Association post in Manang gives daily altitude talks in season, which are worth attending. See our Manang rest-day hikes.
Thorong Phedi or High Camp
Many guides prefer Thorong Phedi for a safer profile, even though it means a longer pass day. High Camp reduces the pass climb but raises the sleeping altitude by 400 m. If you choose High Camp, make sure you feel well at Phedi first. If you have a headache, nausea or poor sleep, stay at Phedi.
Warning signs and decisions
- Headache that does not respond to rest, fluids and simple pain relief: do not go higher.
- Loss of coordination, confusion or severe breathlessness at rest: go down at once.
- Persistent cough with frothy sputum: urgent descent and medical help.
- If a group member is unwell, the group waits or descends together.
Descent is the main treatment. Medication may help some people, but only a doctor can advise you on that.
Hydration and diet
Drink three to four litres a day, eat carbohydrate-rich meals, and avoid alcohol until you are back below 3,500 m. See our blog on staying hydrated and purifying water in the Himalayas.
If you arrive by road at a high start
A road start at Chame or Manang means you skip several days of natural acclimatisation. If you do this, plan an extra rest day and follow the same sleeping profile. Our road and jeep sections guide explains the trade-offs.
If you are already acclimatised
Trekkers who live at altitude, or have just completed another high trek, may feel strong sooner. They still benefit from a rest day in Manang and a gradual rise to the pass. Previous adaptation fades within a couple of weeks at low altitude.
Common questions
How many nights should I spend in Manang?
Two nights with one full rest day is the usual minimum, three if you feel the altitude or plan to add Tilicho Lake.
Is Thorong Phedi or High Camp better?
Thorong Phedi is safer for acclimatisation. High Camp shortens the pass climb but raises sleeping altitude by about 400 m.
What if I feel unwell on the pass?
Descend. No schedule is worth risking altitude illness. Your guide should make the call with you.
What our guests say
Excerpts from trekker reviews on our reviews page.
“Superb trek lead, fantastic experience, perfect weather prediction, had a great knowledge on all peaks.”
