Mount Rinjani (S 08 Deg. 25.000’, E 116 Deg. 28.000’) is an active volcano on the Indonesian island Lombok. It is a massive Caldera structure with a new volcano, the Gunung Barujari, inside the Caldera. The crater lake Segara Anak lies at about 2000 m. The most recent eruptions were on May 22nd and 23rd following earthquakes and ash clouds reaching up to 5000 meters. A major series of eruption dates back to 1994/95. Historical eruptions date back only to 1847, due to the remoteness of the region.
You can approach Mount Rinjani setting off at Senbawulun (S 08 Deg 21.481’, E 116 Deg. 31.275’) at about 1200 m. The first half of the day leads through savanna until the pine mountain forests are reached. After passing the clouds a good base camp site is on the caldera rim at 2700 m (S 08 Deg. 23.599’, E 116 Deg. 26.430’). To get to the Mount Rinjani Summit from here needs about 4 hours. For seeing the sunrise (now 6:34 am) it needs starting at 2:30 am. Even in moonlight (moon setting now at 3:51 am) it is hard to spot walkable trails and the first hour goes through loose rubble. The last 300 meters are ascending through loose volcano ashes which is constantly sliding backward. Passing this is extremely exhausting. The view from the summit at sunrise is tremendous: on one side the sunrise over the island of Lombok, the three Gili Islands and the Lava landscape - on the other the caldera with the intense blue lake and the smoking Gunung Barujari.
Returning to the base camp then is more about sliding down in the ashes than walking. From here, there is a steep trail down the inner side of the crater leading to the lake Segara Anak. The solid rocks are a welcome change to the ashes and rubble from the morning hike to the summit. In the crater are hot springs, which are also a treat and there is a local belief that they treat all kinds of sicknesses. For me they relieved me from the fact of not having a shower for 3 days, climbing and hiking since 2:30 am and being 5 kg too heavy.
The Gunung Barujari sometimes rumbles and then clouds are expelled. Hindus come to the lake and put a life cow on a bamboo raft which they push out to the lake. After a while the raft sinks and the cow, which is tied to it, drowns alive. This explains that there are here and there beef bones in the shallow shore water of the lake.
The climb out of the crater on the other side is steep and needs careful steps. An Italian woman died here a few weeks ago. The view back into the crater is amazing again and when reaching the rim at 2500 m you have a full view of the volcano, the caldera and the summit. Descending from here you enter a rainforest from about 2100 m, which is full of grey monkeys. Best is too keep moving until exiting it again, because there are leaches. At 800 m (S 08 Deg. 18.283’, E 116 Deg. 24.053’) you reach Senaru which is a good camp site.
The island of Lombok will next year get an international airport. Currently there is only a local hub. The connection to Denpasar on Bali is flown on brilliant planes like the Fokker 50. When flights are cancelled, there is a ferry connection which takes 5 hours and also a fast boat in the mornings which makes it in 2 hours. The ferry services are unreliable and usually depart late to give thieves a chance to jump on the boat, steal something and jump off again. Engines sometimes catch fire, which at least delays the journey. If you happen to arrive with a ferry at night, be aware that all transportation (and the prices) are controlled by a few mafiosi in black leather jackets. Keep your knife open in the pocket, but try to stay in safe margins, because the situation is complex and people are skillful, numerous and know the local situation better.