Summit · 8 September 2026
The oxygen arithmetic of 5,000 metres
Altitude is a number before it is a feeling. Air pressure falls with height, oxygen falls with it, and the body adapts at a rate that has been measured for decades. The Altitude Simulator applies the arithmetic to your nights; this is the arithmetic.
Summit · Bhutan
Bhutan, Jomolhari trek
Bhutan charges a daily fee that keeps the trails empty, and the Jomolhari trek is the reward: eight days from the Paro valley to the base of a 7,326 metre peak, over two passes near 5,000 metres, with yak herders and blue sheep for company.
Best window: April to May for rhododendrons, October to November for clear skiesDays needed: 8 to 10
Bhutan let in its first tourists in 1974 and has rationed them by price ever since, and the trails are the beneficiaries. The Jomolhari trek climbs from the Paro valley through forest to a camp at 4,080 metres under a 7,326 metre peak, then crosses two passes near 4,900 to reach Thimphu by another valley. Yak herders, blue sheep, a ruined fortress on the moraine and, in eight days, perhaps two other groups. Everything is carried by horses and cooked by a crew, which is how the kingdom runs its mountains.
What the model says
Two windows either side of the monsoon. April and May bring rhododendrons and afternoon cloud; October and November bring the clearest skies of the year and camps at minus ten. From June to September the passes are in cloud and the trails in leeches. The Altitude Simulator matters here as much as in Ladakh: Jangothang is a high camp reached in two walking days, and the acclimatisation day before the pass is the difference between seeing the mountain and seeing the inside of a tent.
What the ground says back
The daily fee sets the budget band and it is what it looks like: a country that has decided how much tourism it wants. In exchange the trek is fully serviced, the crews are professional and the mountains are empty. The Tiger’s Nest walk on the first day is the right warm-up. The Nyile La day is long and cold and the finest of the eight. Bring the warm bag the operator lists; the one they lend is for the valley.
Days
Eight days of trekking plus two in the valleys: ten days in the country. The longer Laya route adds five days and a second sacred mountain, and the Snowman trek beyond that is three weeks and one of the hardest walks in the Himalaya.
A sample day
- 06:00Tea brought to the tent at Jangothang, frost on the fly sheet
- 07:30Acclimatisation walk up towards Tsophu lakes, Jomolhari filling the sky
- 10:00Blue sheep on the scree, a herder’s yaks grazing the last grass
- 12:30Back at camp for lunch, the sun finally warm
- 14:30Walk to the ruined dzong on the moraine, prayer flags snapping
- 17:00The peak turning gold, then grey, then the cold arriving as if switched on
- 18:30Dinner in the mess tent, the cook producing a cake at 4,000 m
- 20:00Stars, then the tent; the night is long and the bag is warm
A sample plan · 8 days
- Day 1Fly into Paro, the Tiger’s Nest monastery walk to start the legs.
- Day 2Drive to Shana and walk to Thangthangka through the forest.
- Day 3Thangthangka to Jangothang, the trees thinning, the mountain appearing.
- Day 4Acclimatisation day at Jangothang below Jomolhari.
- Day 5Over the Nyile La at 4,870 m to Lingshi, the highest day.
- Day 6Lingshi to Shodu below the Yeli La.
- Day 7Shodu to Barshong along the Thimphu river gorge.
- Day 8Barshong to the road head and Thimphu.
- 10.6hJan
- 11.2hFeb
- 12hMar
- 12.8hApr
- 13.6hMay
- 13.9hJun
- 13.7hJul
- 13.1hAug
- 12.3hSep
- 11.4hOct
- 10.7hNov
- 10.4hDec
What can go wrong
- ▲▲▲AltitudeJangothang camp is at 4,080 m and the passes near 4,900; the itinerary has an acclimatisation day for a reason.
- ▲▲ColdNights at Jangothang drop to minus ten in November; a proper down bag, not a summer one.
- ▲▲WeatherSnow can close the passes in either window; operators carry a plan B down the valley.
- ▲▲RemotenessHorses carry the loads and the emergency plan is a horse; helicopter rescue exists but takes time.
Getting there
Fly into Paro on one of the two Bhutanese airlines, one of the most dramatic approaches in aviation. All treks run through licensed operators with guide, cook and horsemen; the Jomolhari route starts at Shana above the Paro valley and the standard version returns over the Bonte La to Thimphu in eight days.
Hub Paro airport, flights from Delhi, Kathmandu, Bangkok, Singapore
Permits Visa and the Sustainable Development Fee of 100 US dollars per person and night, arranged by the operator; the trek permit is included in the package.
Avoid June to September is monsoon: leeches, cloud and closed passes.
Questions people ask
Why is Bhutan so expensive?
The Sustainable Development Fee is 100 US dollars per night on top of the operator’s package. It funds the country’s free healthcare and education and keeps the trails empty, which is what you are paying for.
How hard is the trek?
Eight days with two passes near 4,900 m and camps above 4,000. Moderate distances, real altitude, full support. A fit walker with an acclimatisation day manages it; the Altitude Simulator shows the profile.
Can I trek independently?
No. Every trek runs through a licensed operator with a guide, and the horses and crew are part of the system.
Field Notes
Summit · 8 September 2026
The oxygen arithmetic of 5,000 metres
Altitude is a number before it is a feeling. Air pressure falls with height, oxygen falls with it, and the body adapts at a rate that has been measured for decades. The Altitude Simulator applies the arithmetic to your nights; this is the arithmetic.
Summit · 25 August 2026
Training for a trek in twelve weeks
Fitness for a trek is built in weeks and lost in weeks, and the plan that works is boring: three walks a week, one long one at the weekend with the loaded pack, stairs for the descents, and a lighter week every fourth. The Training Simulator builds it backwards from your date.
Money · 2 September 2026
The cost of remoteness
The places on this site range from forty-five euros a day to two and a half thousand, and the difference is mostly distance from a road. Here is where the money goes, why, and how the same place can be reached at a fifth of the price.
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