Altitude on Rinjani
Key elevations on the mountain:
- Sembalun trailhead: 1,156m
- Crater rim camp: 2,641m
- True summit: 3,726m
Above 2,500m, the body notices the reduced oxygen. Most trekkers feel fine at the crater rim. The summit push — to 3,726m — is where altitude becomes a real factor.
What is altitude sickness?
Acute Mountain Sickness (AMS) occurs when the body ascends faster than it can adapt to lower oxygen levels. It is not a sign of weakness. Fit, experienced climbers get AMS; beginners sometimes do not.
Mild symptoms: headache, nausea, fatigue, poor sleep, loss of appetite. These are common at crater rim camp and often resolve with rest and hydration.
Serious symptoms (HACE/HAPE): severe disorientation, inability to walk straight, dry cough with pink foam. These require immediate descent and are rare at Rinjani's altitude.
The only treatment for worsening AMS is descent. All guides are trained in first aid and will not allow a trekker to ascend if symptoms are severe.
How to reduce altitude risk
- Stay well hydrated — at least 3–4 litres of water per day on the mountain. (Provided.)
- Ascend slowly. Do not rush the first day.
- Avoid alcohol for 48 hours before the trek.
- Eat well. Appetite decreases at altitude — eat anyway.
- Sleep at the crater rim (2,641m) before pushing to the summit. This gives the body time to adapt.
- Communicate with your guide. Tell them if you feel unwell.
Temperature at altitude
At the crater rim camp (2,641m), nights reach 5–10°C. At the summit (3,726m) before dawn, temperatures can drop to 0–4°C with wind chill making it feel colder. A warm mid-layer and windproof jacket are essential. Sleeping bags, sleeping mats, and tents are provided.
How to prepare physically
The trek involves 8–12 hours of walking per day on uneven volcanic terrain. Preparation makes a significant difference to enjoyment. Start 4–6 weeks before your trek.
Cardio
Run, cycle, swim, or use a stair machine 3–4 times per week. Build up to 60-minute sessions. Sustained aerobic output is what the mountain demands.
Leg strength
Squats, lunges, step-ups. Your quads and glutes bear the load on the descent. Strong legs make the difference between a hard day and a very hard day.
Practice hikes
Walk uphill with a 5–7kg daypack for at least 2–3 hours. Stairs are an excellent substitute if you are not near hills. Get your feet and joints used to the motion before you arrive.
Core
A strong core reduces fatigue on the long climbs. Planks, dead bugs, and carries work well. Twenty minutes three times a week is enough.
You do not need to be an athlete. Consistent moderate exercise in the weeks before is enough for most people to complete the trek comfortably.
Who should be cautious
- Anyone with cardiovascular or respiratory conditions should consult a doctor before trekking above 2,500m.
- Trekkers with a history of altitude sickness should inform the guide team in advance.
- Pregnant women should not trek to altitude.
- Children under 12 are not recommended for the summit route.
If you have any health concerns, message the team before booking. They will advise honestly.