At 10am on August 27, 1883, an explosion equivalent to 10,000 Hiroshima atomic bombs rent Krakatau island; the boom was heard as far away as Sri Lanka. As the eruption column towered 40km into the atmosphere, a thick mud rain began to fall over the area, and the temperature plunged by 5?C. Tremors were detected as far away as the English Channel and off the coast of Alaska. One single tsunami (pressure wave) as tall as a seven-storey building, raced outwards, erasing 300 towns and villages and killing 36,417 people; a government gunboat was carried 3km inland and deposited up a hill 10m above sea level. Once into the open sea, the waves travelled at up to 700kph, reaching South Africa and scuttling ships in Auckland harbour. Two-thirds of Krakatau had vanished for good, and on those parts that remained not so much as a seed or an insect survived.

Today, the crumbled caldera is clearly visible west of the beaches near Merak and Carita, its sheer northern cliff face soaring straight out of the sea to nearly 800m. But it is the glassy black cone of Anak Krakatau , the child of Krakatau volcano, that most visitors want to see, a barren wasteland that's still growing and still very much active. It first reared its head from the seas in 1930, and now sits angrily smoking amongst the remains of the older peaks. To get here requires a motorboat trip (4-6hr) from Labuan or Carita, then a half-hour walk up to the crater, from where you can see black lava flows, sulphurous fumaroles and smoke. The easiest way to visit Krakatau is with the Black Rhino tour company in Carita or through the Beringin Hotel in Kalianda on Sumatra . If you have your own group, inquire at the PHPA parks office in Labuan and see if they can fix you up with a boat, which should cost around Rp500,000 for the day. Bring lots of water and some food (include emergency supplies).