Trekking Mount Rinjani: what to know before you go

Mount Rinjani, at 3,726 metres Indonesia's second-highest volcano, is the great adventure of Lombok: a demanding multi-day trek to a crater rim, a sacred lake and hot springs, with sunrise views that reach as far as Bali. It is genuinely hard, genuinely rewarding, and worth preparing for. The routes. Most treks start from Senaru in the north or Sembalun in the east. Sembalun gives easier access to the summit; Senaru is the classic crater-rim and lake route. Options run from a two-day, one-night rim trek to a three-day traverse taking in the summit, the crater lake (Segara Anak) and the hot springs. Fitness and conditions. This is not a casual hike. Expect long days, steep loose scree near the summit, cold nights at altitude and very early starts for sunrise. A reasonable level of fitness and broken-in footwear make a big difference. The mountain typically closes in the wet season, roughly January to March, and around extreme weather, so check before you plan. Guides and permits. You must trek with a licensed guide and porters, and pay the national park entrance fee. Reputable operators handle permits, food, tents and the climb itself; choose one with good safety practices and fair treatment of porters rather than the cheapest quote. What to bring. Layers for cold summits and warm days, a headtorch, sun protection, plenty of water and snacks, and some cash. Porters carry the heavy gear, but you carry your own day pack. Respect the mountain. Rinjani is sacred to the Sasak and Balinese, and a fragile environment under pressure from its own popularity. Carry out everything you bring in, and stick to the trails. If a multi-day climb is too much, the lower trails and waterfalls around Senaru offer a taste of Rinjani's scenery for far less effort, and still some of the best views on the island.