Altitude sickness can occur above 2,500 m, and the crater rim camp sits at 2,641 m. Mild symptoms such as headache, fatigue and poor sleep are common there, and usually resolve with rest and hydration. The summit push, to 3,726 m, is where altitude becomes a real factor. Here is what to expect, how to prepare, and what to do if symptoms appear.
The numbers
Above 2,500 m the body notices the reduced oxygen. Most trekkers feel fine at the crater rim, and the difference is felt on the summit push.
At the crater rim camp, nights reach 5–10 °C. At the summit 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.
What altitude sickness actually is
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
Common at crater rim camp, and they often resolve with rest and hydration.
- Headache
- Nausea and loss of appetite
- Fatigue and poor sleep
Serious symptoms (HACE/HAPE)
These require immediate descent, and are rare at Rinjani’s altitude.
- Severe disorientation
- Inability to walk straight
- Dry cough with pink foam
The only treatment for worsening AMS is descent. Your guide has walked this mountain hundreds of times, watches for symptoms on the way up, and will not let you continue if they are severe.
What lowers the risk, and who should take care
Most of it is in your hands: how fast you go up, how much you drink, and whether you sleep at the rim before the summit.
What lowers the 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. None for 48 hours before the trek.
- Eat well. Appetite decreases at altitude: eat anyway.
- Sleep at the crater rim. A night at 2,641 m before pushing to the summit gives the body time to adapt: the 3-day summit and lake route builds in this overnight stop.
- Communicate with your guide. Tell them if you feel unwell.
Who should be cautious
- Cardiovascular or respiratory conditions. Consult a doctor before trekking above 2,500 m.
- A history of altitude sickness. Inform the guide team in advance.
- Pregnancy. Pregnant women should not trek to altitude.
- Children under 12. Not recommended for the summit route.
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, and matters most on the direct 2-day summit challenge. 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.
Add practice hikes uphill with a 5–7 kg daypack, 2–3 hours at a time, and twenty minutes of core work three times a week. 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. The full six-week build-up is on the training plan.
"Our guides Zain and Aman were so kind and funny, making sure we had plenty of time to rest and recover."
Frequently asked questions
How high is Mount Rinjani?
Mount Rinjani reaches 3,726 metres (12,224 feet), the second-highest volcano in Indonesia and the third-highest peak in the country. The crater rim camp sits at approximately 2,641 metres.
Can you get altitude sickness on Rinjani?
Yes. Altitude sickness (AMS) can occur above 2,500 metres. Most trekkers experience mild symptoms such as headache or fatigue at crater rim camp (2,641 m). Serious altitude sickness is uncommon but possible at the summit (3,726 m). Guides know the signs from hundreds of ascents and descend immediately if needed.
How fit do you need to be to trek Rinjani?
A moderate level of fitness is needed for the crater rim. The summit push requires good cardiovascular fitness. You should be comfortable walking uphill for 5–8 hours continuously. Training is recommended: start 4–6 weeks before your trek with regular cardio, stair climbing, and loaded pack hikes.
What are the symptoms of altitude sickness on Rinjani?
Common AMS symptoms: persistent headache, nausea, dizziness, loss of appetite, fatigue, and disrupted sleep. If symptoms worsen, the only effective treatment is descent. Do not ascend further with AMS symptoms. Your guide will monitor the group throughout the trek.
Not sure how altitude will treat you?
If you have any health concerns, message the team before booking. They will advise honestly.