Gunung Rinjani

Date: September 5-6, 2026

Distance: 25km

Elevation gain: 2100 m

Mount Rinjani, a dormant volcano, is the highest peak on the island of Lombok. It is 3,726 metres tall, making Lombok the eighth highest island in the world. The mountain rises above a caldera, created by a massive eruption in 1257. Its bright blue lake is called Segara Anak - “Child of the Sea” - and contains its own volcanic cone.

The mountain is not technical, but it’s a long slog, especially the last few hundred metres on volcanic scree. As with other major Indonesian mountains, guides are mandatory. It’s usually done as a 3 day or 2 day trek. Some of the longer treks take you inside the crater to see hot springs. There is one guide who will take strong hikers to the summit and back in one day (see Peakbagger for details), but for bureaucratic reasons this costs the same as a two day ascent. It's also possible to trek to the crater rim, which is much easier than the summit. Either way, this mountain is not for the faint of heart. 

Rinjani was one of the main objectives of my Indonesia trip. After climbing Mount Tambora, Shaojie and I got back to civilization and cell service, only to learn that the national park containing Rinjani was about to close, and that they were only allowing bookings made before midnight. It was a race against time to secure permits. 

We’d planned to do the hike in 1 day, but we ended up booking a 2 day, 1 night package with John Adventures https://rinjanihike.com/ who could guarantee a booking. John was the first guide on Rinjani and Steven Song had used this company on his Rinjani climb so we were in good hands. 

We flew to Lombok. Then next day we were picked up and taken to Senaru, a village in the north of the island on the slopes of Rinjani. After a short briefing, I wandered around the village for a while. It's a very pleasant place with views of the mountain and the ocean. The Sendang Gile and Tiu Kelep waterfalls were highlights. 

Shaojie and I had dinner at a restaurant with mountain views.  

The next morning we woke up and met the rest of the group: nine hikers in total from Canada, Australia, the US, Belgium, Germany, and Malaysia. All nine of us got into the back of a pickup truck and drove towards the trailhead. Our first stop was a sort of clinic in Senaru where we all got blood pressure tests and a medical certificate. We also met our guides. 

Then we drove an hour east to Sembalun. As the truck accelerated, Shaojie’s hat flew off. The drive was exciting, with a few steep sections.

We stopped at a ranger station and some more paperwork was filled out. Then we were off to the trailhead to finally start our hike. 

The trail initially went through some cow pastures, with cows grazing beside the trail.

A short section of forest provided a reprieve from the hot temperatures, but that was over soon and we went back into the open. 

The trail was quite busy with hikers, guides, and porters. 

We were asked to take a long break at pos (rest stop) 2, moving a few times since it was unclear what the plan was. It turned out that the porters were making lunch for us. The food was surprisingly good for a camping trip, as was the case for all our meals. 

There were some monkeys hanging around the shelters. We had to be careful with our food. One monkey helped himself to a bowl of noodles underneath a shelter. 

At pos 2 we also had a permit check. Rangers went through our backpacks: to reduce littering, wet wipes and canned food are prohibited. To their credit, Rinjani has much less trash than other Indonesian volcanoes, although it’s still quite polluted by western standards. 

As we left, fog rolled in. 

We took another long break at pos 3, with its own resident monkeys. One monkey snuck underneath the seats and stole a bag of chips from my backpack!

The trail got steeper and dustier from there. At one point the clouds cleared, revealing the summit ridge, still over a kilometre above us. 

We reached the campsite on the crater rim around mid-afternoon. The lake was covered in clouds. Around sunset we had curry for dinner. As before, there were monkeys everywhere and we couldn't leave food unattended. Sunset over the crater was spectacular. 

The next morning, the alarm went off at 1:30am and we began the long climb to the summit. This was divided into three parts, each taking about an hour. The first was a steep grind up dusty slopes to a ridge. Once on the ridge, the route became much less steep, but there was a yawning drop-off to our right. In the dark it was impossible to see how far down the cliff went. It was quite windy at this stage and we often found ourselves taking shelter behind walls. I was quite a bit ahead of the group so I took a long break in an especially sheltered area. 

The last couple hundred metres were the hardest. It was fine volcanic scree with a few larger rocks. For every two steps forward, you slid one step back. The high altitude did not help matters.

Eventually the terrain flattened out and I arrived at the summit a few minutes before sunrise. As expected, there were many people, but it's a wide summit and there was room for everyone. 

From the summit, I could see basically all of Lombok, especially the impressive caldera and the Child of the Sea.  Mount Agung on Bali and Mount Tambora on Sumbawa were visible in the distance. I’d seen Rinjani from both of those peaks and now I was there. 

The sun rose directly behind Tambora.

After sunrise we made our way down to the campsite and had breakfast. I had a long nap.

The descent was slow and steady. Like other Indonesian volcanoes, the upper part of the trail was dusty and slippery and we found ourselves often holding on to trees. At each of the pos shelters, we would take very long breaks. It was the most leisurely descent I’ve ever done, but that wasn't too bad on such a consistently steep trail. We had lunch at pos 2, again avoiding the monkeys. 

We made it to the trailhead, drove back to the ranger station to sort out some more paperwork, then drove back to Senaru, once again in the bed of the truck. Somehow one of us fell asleep on the drive. Once at the clinic in Senaru, we picked up our luggage and said our goodbyes. 

This was a beautiful mountain climbed with great people. It was the perfect end to the Indonesia trip.