Mount Rinjani's volcanic cone rises 3,726 metres above Lombok, making it Indonesia's second-tallest peak and the highest point in the Lesser Sunda Islands.
The stratovolcano last erupted in 2016, sending ash plumes four kilometres into the atmosphere and closing the mountain for eight months while trail infrastructure was rebuilt. Today the Rinjani Trek Centre in Senaru and Sembalun villages manages all permitted ascents through Mount Rinjani National Park, a 41,330-hectare conservation zone established in 1997 to protect submontane forests, the endangered ebony leaf monkey, and 109 bird species including the yellow-crested cockatoo.
The mountain's caldera holds Segara Anak, a crescent lake 2,000 metres above sea level and six kilometres across, its turquoise water fed by underground springs. Within the lake rises Gunung Barujari, an active cone that emerged after Rinjani's 1257 eruption—one of the most powerful volcanic events in recorded history, believed to have triggered global cooling and crop failures across Europe. Geothermal vents along the eastern shore produce natural hot springs, their sulphurous water pooling at 40 degrees Celsius year-round. Sasak and Balinese pilgrims have climbed Rinjani for centuries to leave offerings at the crater rim during the annual Pekelan ceremony, held each full moon between October and December.
Most mount rinjani trekking packages depart from Sembalun village at 1,150 metres elevation, following the southeastern ridge through savannah grasslands and Casuarina forests before ascending the exposed scree slope to Rinjani's summit. The alternative Senaru route enters from the north, descending directly into the caldera to camp beside Segara Anak before the final summit push. Both trails converge at Pelawangan II, the 2,700-metre saddle where trekkers stage pre-dawn summit attempts. The conservation fee of 250,000 IDR per person per day funds trail maintenance, porter welfare programs, and reforestation projects replanting endemic species like Vatica umbonata and Ficus species across fire-scarred slopes.
The 2016 earthquake damaged 80 percent of Rinjani's trails, prompting the park authority to implement new campsites with permanent toilet facilities and designated cooking zones at Pelawangan I, Pelawangan II, and Segara Anak. Park gates open at 07:00, and all trekkers must register at checkpoints in Senaru or Sembalun before departure. The dry season from May through October offers the clearest weather, though afternoon cloud build-up obscures summit views after 14:00 most days.
48 hr
