Mount Rinjani: The Throne of the Gods

Domination. That is the only word to describe Mount Rinjani (Gunung Rinjani). Rising 3,726 meters (12,224 feet) above sea level, massive volcano dominates the entire northern half of the island of Lombok. It is the second-highest volcano in Indonesia (after Mount Kerinci on Sumatra) and arguably the most spectacular trekking destination in Southeast Asia.

Rinjani is not just a mountain; it is a complex geological system comprising a soaring summit, a massive 6-by-8.5 km caldera, a crescent-shaped crater lake named Segara Anak, and an entirely new active volcano, Gunung Barujari, growing inside that lake.

A Mountain of Two Faiths

Like its neighbor Mount Agung in Bali, Rinjani is revered as a sacred site.

• For the Sasak People: The indigenous Sasak people of Lombok believe the mountain is the seat of the gods and spirits. Every year, during the Mulang Pakelem ceremony, hundreds of pilgrims trek to the crater lake to make offerings of gold, jewels, and buffalo heads to the spirit of the mountain, Dewi Anjani.
• For Balinese Hindus: Rinjani is considered one of the three sacred mountains (along with Agung and Bromo). Balinese Hindus believe the crater lake is spiritual ocean, and water from the lake is often collected for use in high religious ceremonies back in Bali.
• Religious Closures: The mountain is closed to hikers during major religious ceremonies, particularly in April. Always check the calendar.

The Impact of the 2018 Earthquakes

In July and August 2018, Lombok was struck by a series of powerful earthquakes (up to magnitude 6.9). The epicenter was near the northern slopes of Rinjani.

• Landslides: The quakes triggered massive landslides that destroyed the main trails from Senaru. Hundreds of hikers were stranded on the mountain and had to be evacuated in a dramatic rescue operation.
• The Healing Process: For nearly a year, the mountain was closed. The trails have since been rebuilt and are safer, but scars on the landscape—and the destroyed homes in the village of Senaru—are still visible. Visiting and hiring local guides is the best way to support the economic recovery of these resilient communities.

The Legend of Dewi Anjani

The name “Rinjani” is believed to come from an old Javanese term meaning “God”. The presiding spirit of the mountain is Dewi Anjani, a princess-turned-spirit queen.

• The Origin Story: Legend says Dewi Anjani was the daughter of a priest who was turned into the ruler of the massive mountain kingdom of spirits. She resides in a palace visible only to the spiritually pure, located near the Segara Anak lake.
• The White Animals: It is said that Dewi Anjani keeps many pets. Hikers occasionally report seeing white fish in the lake or white deer on the slopes—these are believed to belong to the Queen and must never be harmed.
• Offerings: The small gold squares often found at the lakeside are offerings thrown into the water by Balinese pilgrims to appease her and ask for blessings of fertility and prosperity.

To climb Rinjani is to walk through a cathedral of nature, where the smell of sulfur mixes with the scent of incense left by pilgrims.

The Geology of Destruction and Rebirth

The Rinjani we see today is actually the rebuilding of an even larger ancient volcano known as Samalas.

The Samalas Eruption of 1257

In 1257 AD, Samalas—which was likely over 4,200 meters high—erupted in one of the most violent events in the Holocene era (VEI 7).

• Global Impact: The eruption ejected so much sulfur into the atmosphere that it caused a “Little Ice Age” effect globally. Ice core samples from Antarctica and Greenland show massive sulfur spikes from this year. Medieval chronicles in Europe record “unendurable cold” and failed harvests the following year, which scientists have now linked directly to this eruption in Lombok.
• The Collapse: The eruption emptied the magma chamber, causing the massive mountain to collapse, forming the caldera we see today.

The Birth of Barujari

Inside the caldera, life began again. As the hole filled with water to form Lake Segara Anak, a new vent opened on the lake floor.

• The New Mountain: Over centuries, this vent built a new cone. It is called Gunung Barujari (meaning “New Mountain”). It is the active child of the old giant.
• Recent Activity: Barujari is highly active. Major eruptions occurred in 1994, 2004, 2009, 2015, and 2016. During the 2015 eruption, the ash cloud forced the closure of airports in Lombok and Bali for days. When you trek Rinjani, you are looking down at a volcano that is very much alive.

Segara Anak: The Child of the Sea

The jewel of Rinjani is Segara Anak (“Child of the Sea”).

• The Color: The lake is named for its intense blue-green color, reminiscent of the sea.
• The Depth: It is roughly 200 meters deep and sits at an altitude of 2,000 meters.
• Thermal Dynamics: Despite being at a high altitude where the air is chilly, the water temp is moderated by thermal vents. In certain bays near the base of Barujari, the water bubbles with heat.
• Hot Springs: Near the lake’s campsite, there are natural hot springs (Aik Kalak). These are the ultimate reward for trekkers. Soaking in 40°C sulfur water after two days of grueling hiking is a luxury that no 5-star spa can match.

The Trekking Experience

Hiking Rinjani is often cited by world travelers as one of the best treks in Asia, but it is physically punishing. It is not a walk in the park; it requires high fitness and mental stamina.

The Routes

There are two main gateways: Senaru (in the north, 600m) and Sembalun (in the east, 1,100m).

• Classic 3D/2N Traverse: Most trekkers start in Sembalun and end in Senaru.
  • Day 1: Sembalun to Rim II (Sembalun Crater Rim). This is a long day of walking through savanna grasslands which offer little shade, ending with a steep ascent to the campsite at 2,639m.
  • Day 2 (The Summit Push): Waking up at 2:00 AM for the summit attack. This is the hardest part of the trek. You climb 1,000 meters on loose volcanic scree (gravel). For every two steps up, you slide one step back. Reaching the 3,726m summit at sunrise offers views of Agung in Bali, Tambora on Sumbawa, and the Gili Islands below. Afterward, you descend into the crater to the lake for lunch and hot springs, then climb up the other side to Senaru Rim.
  • Day 3: Descent from Senaru Rim through thick tropical rainforest to Senaru village.

What to Expect

• The Porters: The true heroes of Rinjani are the local porters. Wearing flip-flops (or sometimes barefoot), they run up the mountain carrying 30-40kg baskets attached to bamboo poles. They carry tents, sleeping bags, food, water, and cooking equipment. They will have tea ready for you before you even reach the campsite.
• The Trash Problem: Rinjani has suffered from its own popularity. Plastic waste is a major issue. Responsible trekking companies now enforce a “pack it in, pack it out” policy, and some organize cleanup treks. As a visitor, you must ensure you leave zero trace.

Flora and Fauna

Rinjani National Park sits on the Wallace Line, the biological boundary between the ecozones of Asia and Australia.

• The Forests: The lower slopes are covered in lush dipterocarp forests, rich in figs and orchids. As you ascend, this gives way to Casuarina forests (resembling pine trees) and eventually alpine grassland.
• Wildlife:
  • Ebony Leaf Monkey: You might spot the shy, silver-haired Lutung monkeys in the trees near Senaru.
  • Long-tailed Macaque: The more aggressive grey monkeys are common at the rest stops and crater rims, essentially waiting to steal your snacks.
  • Rinjani Scops Owl: A rare owl endemic to this specific island.

Best Time to Climb

• April to December: This is the dry season and the official climbing season.
  • Peak Season: July and August. The weather is dry, but the trails are crowded. Only book well in advance.
  • Shoulder Season: April-May and October-November. Rain is more likely, but the crowds are thinner and the mountain is greener.
• January to March: The park is usually closed due to heavy monsoon rains which make the trails dangerous and prone to landslides. This also gives the ecosystem time to recover.

Technical Facts at a Glance

• Location: North Lombok, Indonesia
• Coordinates: 8.41°S 116.46°E
• Elevation: 3,726 m (12,224 ft)
• Prominence: 3,726 m (It rises directly from sea level)
• Caldera Dimensions: 6 km x 8.5 km
• Lake Elevation: ~2,000 m
• Last Eruption (Barujari): September 2016
• Volcanic Type: Stratovolcano with Caldera

Conclusion

Mount Rinjani is a place of extremes. The climb pushes your body to the limit, but the reward is a landscape that looks like the dawn of time. Watching the sun rise over the smoking cone of Barujari, reflected in the turquoise mirror of Lake Segara Anak, is a memory that stays etched in the mind forever. It is the king of Lombok, and arguably, the king of Indonesian volcanoes.