Top 10 Volcanoes in Indonesia
Indonesia is the world's most volcanic country, with more than 130 active volcanoes strung along the Sunda Arc. From Sumatra to Maluku, an enormous slab of seafloor dives beneath the archipelago and feeds a near-continuous chain of cones and calderas. These ten anchor the map.
1. Mount Bromo, East Java
The most photographed volcano in Indonesia: a small smoking cone in the middle of the vast Tengger caldera, reached by jeep across the Sea of Sand for sunrise from Penanjakan viewpoint.
2. Mount Merapi, Central Java
"Fire Mountain" looms over Yogyakarta and has erupted dozens of times in the last century. The lower slopes carry villages, temples, and museums remembering the 2010 disaster; the summit is closed during periods of elevated activity.
3. Krakatau, Sunda Strait
The 1883 eruption is one of the most consequential in history. Today the new cone of Anak Krakatau ("child of Krakatau") rises from the same caldera in the strait between Java and Sumatra — visited by boat from Carita or Anyer.
4. Mount Rinjani, Lombok
A 3,726 m stratovolcano with a vast caldera holding Lake Segara Anak and a new active cone rising from it. The multi-day trek is one of Southeast Asia's classics; permits and porters are mandatory.
5. Mount Agung, Bali
The sacred mountain of Bali, central to Balinese cosmology and home to the mother temple Pura Besakih on its slopes. Recent eruptions (2017–19) showed how rapidly air travel and tourism can be disrupted.
6. Mount Tambora, Sumbawa
The 1815 eruption was the largest in recorded history and produced 1816's "year without a summer" worldwide. The huge summit caldera is now a national park reached by multi-day trek.
7. Toba caldera, Sumatra
The largest known volcanic eruption of the past million years left a hundred-kilometre-long caldera, now Lake Toba — the largest crater lake on Earth, with an island (Samosir) almost the size of Singapore inside it.
8. Mount Sinabung, Sumatra
Dormant for centuries, Sinabung became one of the most active volcanoes on Earth from 2010 onward, with repeated pyroclastic flows. Visiting is restricted; the museum at Berastagi tells the story.
9. Mount Kelud, East Java
A small, frequently erupting volcano famous for its blue crater lake and the 2014 eruption that shut down airports across Java. Reachable by road and a short trail in calm periods.
10. Mount Ijen, East Java
The blue-flame volcano of East Java — burning sulphur gases ignite blue at night above the world's largest highly-acid crater lake. Pre-dawn climbs combine the flames with a turquoise sunrise.
Travelling Indonesia's volcanoes
Java, Bali, Sumatra and Lombok between them give the easiest access. The classic route is a fortnight: Krakatau and Anak Krakatau from West Java, Bromo and Ijen across the east, Rinjani in Lombok, Agung and Batur in Bali. Sumatra adds Toba and Sinabung for the more determined.
Hazard, alerts and guides
The Indonesian volcanology agency (PVMBG) operates a four-level alert system. At elevated alert most peaks close their summits; guides are mandatory on many and strongly recommended on the rest. Check the agency's status page the day you go.
See them on the map
Filter the map to Indonesia and the Sunda Arc is laid bare — a volcanic spine 3,000 km long. Pick one island first; the geography is already enormous before you add the climbing.