Krakatoa ("Gunung Krakatau) is a volcanic island between Java and Sumatra in Indonesia.
The eruption of Krakatoa in 1883 was the largest volcanic event on record, a huge explosion as seawater hit hot magma and turned instantly to steam. It has been estimated as 150 megatons. The tsunami was 40 meters high in places. The blast was heard over 4000 km (2500 miles) away (Australia and India) and the dust it blew into the stratosphere affected weather worldwide for several years.
Only about a third of the pre-1883 island survived the blast.
From 1927 to 1930, there were several underwater eruptions on the site of the old Krakatoa volcano. On August 11, 1930, a new active volcano and island appeared. This new volcano is called "Anak Krakatau" ( Child of Krakatoa).
You can reach Anak Krakatoa island by chartering boat from Anyer beach or Carita beach (Banten). Bring your own live vest. The trip takes up to 2 hours.