When Krakatau erupted in 1883, it became the most powerful volcanic eruption in recorded history. Scientists stationed in Batavia (Jakarta) used seismographs to measure the earth’s movements and this information, along with eyewitness accounts, were telegraphed around the world through new transoceanic cables that connected every continent. It was one of the world’s first global news stories.
There were no settlements on Krakatau itself as the ill-tempered island had been rumbling for centuries. However, the nearby coasts of Sumatra and Java were well populated by both Indonesians and foreigners, who were attracted to the rich volcanic soil, the fisheries and the strategic Sunda Strait–a busy shipping lane used for the Dutch spice trade.
The forces that had formed Krakatau Island lay deep within the earth’s crust where the Indo-Australian tectonic plate grinds beneath the Eurasian plate. This subduction process sends island-forming magma to the surface. In 1883, the island actually had three ominous volcanoes: Rakata, Danan, Perbuwatan – and all of them were active. However, the magma chamber had been plugged by viscous rock for hundreds of years and the pressure that built inside intensified until the eventual eruption on August 26, 1883.
It must have been a terrifying sight that afternoon when all three volcanoes erupted, spewing columns of ash and mushroom clouds 50 kilometres into the atmosphere. Pyroclastic flows (fire, debris and gases) ran down the mountainside and across the sea, travelling at over 160 kilometres per hour incinerating everything in their path. For the people in South Sumatra and West Java who witnessed the event, their world turned black and warm and sticky ash began falling from the sky. It must have felt like the end of the world.
Scientists believe that the partially emptied magma chamber was then filled with a hotter, darker magma from deep within the earth, creating a lethal mixture. Gases expanded, pressure increased and by 5:30 the next morning there was a cataclysmic explosion that ripped the island apart.
Over the next four and a half hours, there were two more explosions. The first one was so loud that it was heard in Perth, Australia, 3,200 km to the south and Rodriguez Island 5,000 km to the west.
It reverberated around the globe seven times and to this day remains the loudest sound in recorded history. The next explosion was so powerful that the island literally blew itself to bits and whatever was left standing collapsed into the magma chamber and disappeared into the boiling ocean.
The explosions caused deadly tsunamis. Boats in the Sunda Strait witnessed immense walls of water and the coastlines of South Sumatra and West Java were slammed by mammoth waves up to 40 metres high. By the time the damaged could be assessed, 165 villages had been destroyed and almost 37,000 people had lost their lives.
Today the only thing that remains of the original island of Krakatau is half of the Rakata volcano. Left scorched and devoid of life in 1883, Rakata regenerated at an amazing pace. Algae and ferns took hold within three years. Then grasses appeared. Over time trees took over the grasses, and within 40 years the island was covered in dense jungle. Visitors today can explore the jungle and find two-toned chunks of lava, testimonials of the magma mixing that triggered the massive explosion and tore Krakatau apart.
In 1930 Krakatau proved that it wasn’t finished yet. After three years of churning magma onto the seabed, a new island was born: Anak Krakatau (Child of Krakatau). Regular eruptions have raised Anak Krakatau to the lofty height of 400 metres in less than 90 years – comparable to the height of the Empire State Building.
There are a few black sand beaches strewn with granite and lava rock. Areas undisturbed by volcanic activity are now covered in jungle. Birds sing and cicadas drone in the midday heat. At sunrise one is likely to be greeted by a biawak or two, cousin of the famous Komodo dragon. At dusk retiring egrets and seed-dispersing bats will cast silhouettes against the sunset.
Snorkelers will feel sudden currents of hot water, bump into chunks of floating pumice and get a fascinating look at underwater lava flows. New corals grow from the flows, temporarily providing food and shelter for marine life, waiting to be buried in the next eruption.
Above the jungle is a fascinating transition zone where pioneer species of grasses and trees establish themselves in the sterile ash and rock, laying the groundwork for future forests. Beyond the transition zone looms a barren and foreboding volcano. The trail zigzags upward through silty ash and lava flows of varying colour. Sometimes the ground will feel warm as Anak Krakatau radiates from the inside out. Then the landscape becomes an otherworldly scene: bright yellow fumaroles belching out clouds of toxic sulfuric gas.
From the top of Anak Krakatau, looking out over the ocean at the distant Rakata, it’s difficult to comprehend forces so destructive as to make an island disappear, but gazing into the mouth of the crater one can imagine how it is being reborn.
The best way to see Krakatau is through a travel company:
- Door-to-door service from Jakarta can be arranged.
- Overland to/from Jakarta to Carita or Anyer
- Boat to/from the west coast to Anak Krakatau
- Volcanic activity will determine the trip – be sure to inquire
- Boats do not operate during much of the rainy season
There are three types of trips:
- Day trips including hiking and snorkelling, returning to the west coast or Jakarta on the same day
- Overnight camping trips including hiking and snorkelling staying on Rakata or Anak Krakatau
- One-day dive trips including hiking, returning to west coast or Jakarta the same day
- Visit the ruins of the Fourth Point Lighthouse and see a 600-tonne chunk of coral washed up by the tsunami in 1883
- Visit the hills behind Carita to see what stopped the tsunami from advancing further inland