Mount Bromo
Mount Bromo, at 2329 m, is one of the most iconic mountain in Indonesia. This is due its majestic beauty, where it stands forebodingly within the Tengger caldera sea of sand while spewing off white sulphurous smoke. Mount Bromo is one of the most active volcanoes of the world and one of the frequent visited ones. Travelers come here to view the sunrise over this mountain, where the ethereal landscape is not to be missed.
Mount Batur
Mount Batur is probably one of Indonesia's most popular volcanoes due to its difficult but rewarding hike. Most people chose to do the two-to-three-hour hike of Mount Batur at dawn so they can see the incredible sunrise from the top. It is one of the most popular activities on the island of Bali for those looking for a bit of adventure. This Indonesian volcano is located in a beautiful sprawling caldera and is twinned by Mount Abang on the other side.
Mount Kelimutu
Mount Kelimutu is best known for the tri-coloured lakes perched on its summit. Located at a height of 1,639m (5,377ft), these mystical, colour-changing lakes boast a sweeping mountaintop vista, which looks especially ethereal when paired with the gleaming sunrise. Each of these lakes has its own colour, turning from calming turquoise to pitch black over the years. The hiking trail to Mount Kelimutu’s peak is a rather convenient stairway, start early and bring your Ende-weave sarong to beat the cold.
Mount Semeru
Mount Semeru is the tallest mountain in Java, located at the east. It is also known as Mahameru by the locals which mean The Great Mountain, deriving from the mystical Hindu-Buddhist mountain of Meru and Sumeru the gods. Climbing to the peak takes two hiking days and it is relatively easy for seasoned hikers. The only challenge is the last slope up to the summit. Mount Semeru is an active volcano with constant smokes from its crater.
Mount Merapi
Mount Merapi, or "the mountain of fire" in the local language, is one of the most active Indonesian volcanoes. However, it has quieted down in recent years and can now sometimes be hiked when activity is low. Sometimes you can even arrange a nighttime flight over the volcano so that you can see the lava flowing down its eastern side. If you visit Mount Merapi, you can also see some of the ruins that were formed following the volcano's last large eruption in 2010.
Mount Ijen
Mount Ijen’s irresistible charm lies with the strange, otherworldly blue flames at its caldera. This rare natural phenomenon has summoned adventurers and scientists alike to witness the blue blaze, which is caused by the high concentration of sulphur. This curious occurrence usually happens around 2am and lasts until well before sunrise, concluding your hike on a sweet note with an orange glow as the sun emerges from the darkness.
Mount Tambora
While the eruption of Mount Krakatoa may be quite famous around the world, it was, in fact, the 1815 eruption of Mount Tambora that was one of the deadliest in the world, the largest volcanic explosion ever recorded. It was the cause of the "Year without Summer" in 1816, a series of climate abnormalities that caused temperatures to drop and led to major food shortages around the world. The eruption was believed to kill about 71,000 people and was heard over 2,000 km away. Today, the volcano is calm and safe to hike.