The Booming Blowhole of Kiama
On the coast of New South Wales, the sea is forced into a hole in the rock with a deep boom, and shoots a jet of spray high into the air.
What was reported
At Kiama, south of Sydney, waves rush into a cave beneath a rocky headland and up through a hole in its roof. When the swell is right, the blowhole booms like a cannon and blasts a column of water and spray up to 25 metres into the air, drenching anyone too close.
The explorer George Bass recorded the blowhole in 1797, describing the 'tremendous noise' it made.
Explanations offered
The blowhole formed where the sea eroded a weakness in the volcanic rock, creating a cave whose roof later collapsed partly to make a hole. When a wave fills the cave, the air and water are compressed and forced upwards with great force.
- When
- Recorded by Europeans in 1797
- Where
- Kiama, New South Wales, Australia
- Witnesses
- Visitors for over 200 years
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.
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