Bart Bear's Blog

Near the cabin we stayed at in Kiama there is a fascinating thing. The headland is made of old volcanic rock that the sea has been eroding away for millions of years. In one place it has enlarged a crack in the rock to form a pipe with a big chamber at the end. Some of the roof of the pipe collapsed ages ago, so now when the waves are coming from the right direction something spectacular happens. Waves slam into the entrance of the pipe and compress the air in the end of the pipe and the chamber. When the wave tries to run back out the pipe it sometimes gets blocked by the next wave coming in and the compressed air forces the water up the hole in the roof. There is a loud "whoomp" and the water sprays way up into the air. It was doing this really well while we were there. The blowhole has been on maps of Australia since December 1797 when George Bass was exploring the coast south of the new settlement of Sydney. Of course the aboriginals knew about it for thousands of years before that, and now Scruffy, Milkshake, Blu and I know about it as well.

Labels: New South Wales, south coast