The power of Krakatoa is awe-inspiring, writes Michael Travers.
Let's wait for one more explosion," I said to the captain as I sat on the front of the chartered speedboat bobbing in the calm waters 500m off the south side of Anak Krakatoa.
Ten minutes later there was an almighty sonic boom and the island was engulfed in dust and noise. Chang Loos, our local guide, jumped to the back of the boat so quickly that I started to panic. Immediately, about 300m to port, 1000 volcanic bombs strafed the waters like a Pearl Harbour morning.
Jaws dropped in disbelief as we saw two torso-sized rocks hurtling through the air towards us. There was no time to think before they hit the water less than 20m from our starboard side, throwing huge plumes of water into the air.
Before I even had a chance to exhale, the captain gunned the engines and headed away from there like his life depended upon it. And it did. "Mister, you are very lucky. You almost die," were the exact words I heard before the shakes set in and we all cracked up in nervous laughter.
Krakatoa sits in the middle of the Sunda Strait between Java and Sumatra, and on August 27, 1883, it erupted in a series of violent explosions that almost destroyed the island entirely.
The blast created a huge tsunami, sent 21 cubic km of rock and ash into the atmosphere and the explosion was so violent it was heard on the island of Rodriguez in the Indian Ocean, 4800km away.
Average global temperatures fell by as much as 1.2C as the dust cloud blanketed the earth, creating darkness in Asia and producing stunning sunsets as far away as Europe for months to come. The resulting pyroclastic flows and tsunamis killed more than 36,000 people.
The explosion we saw was not that bad but the danger was not over, because we had planned to land on the island itself.
We circled to the west side and came ashore on a seemingly serene sandy beach. A constant rain of fine ash was falling and covered us and everything around.
After a 10 minute walk uphill, we reached the tree line and a landscape of barren sand and rock slopes covered in volcanic bombs and impact craters.
The volcano was firing out chunks of rock that varied from pebbles to the size of small buses. The many broken branches on the lofty pines were testament to their power. After each successive explosion we could see several bombs landing in the sand around us.
Even from behind the false security offered by the surrounding trees, it was not a comfortable feeling.
During the 1883 eruption, the entire island was destroyed, leaving only three rocky fragments. The active cone that we see today is known as Anak Krakatoa - Child of Krakatoa - and sits in the middle of the deep ocean caldera.
It first appeared above the waves in 1930 and it grew slowly from the depths. It has been growing ever since, thanks to successive eruptions, and has now reached a height of nearly 300m.
Volcanic activity apparently happens in cycles and we happened to be there during a two-year-old upsurge. Indeed, when we visited the seismic laboratory back on the mainland, we saw that there had been 153 eruptions in the past 24 hours.
Rakata, the last surviving remnant of the shattered island, is about 3km south of the volcano and with its calm and secluded beach is the perfect place to watch the volcano by night. The guides set up camp, supplies are brought ashore, fish are caught and a fire is made in preparation for the evening's entertainment.
We sit and stare into the blackness for hours, watching the sky light up as the magma erupts high out of the volcano and snakes down the sides of the mountain like a melting ice cream. This sky show never stops and I am woken constantly from my sleep by another fireworks spectacular.
As we leave the next morning we skirt close to the volcano again to see what changes have been made overnight. I see a boulder the size of a bus three-quarters of the way down the western flank, obviously one of the huge red embers we saw being discharged during the night.
It is a further reminder that Krakatoa is the outlet for an awesome power. Fail to show it proper respect and you could end up paying for it with your life.
Further information: To experience Krakatoa contact Java Rhino Eco-Tour Indonesia, a group endorsed by the World Wildlife Fund and dedicated to saving endangered wildlife and threatened cultures. Email firstname.lastname@example.org