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The mystery of the Pittwater pyramids

a bridge over a body of water

It may be easy to overlook these pyramids around Bayview in Sydney’s north but they are in fact some of the last remaining structures from World War II.

From 1941 to 1942, the Federal Government aimed to protect mainland Australia and ensure that they had adequate defenses in place to defend the area from Japanese invasion.

Allied Works Council were formed who were to protect the area by putting different measures in place. The pyramids are actually concrete tetrahedron tank traps and were one of the defenses put in place, along with blackout laws, barbed wire across our beaches and submarine boom nets.

The Northern Beaches was identified as particularly susceptible to land invasion so approximately 300 of these tank traps were installed around Pittwater with the first eight being placed on Fairy Bower Beach in Manly. Each trap was five feet high and weighed about two tonnes!

Today, only a few remaining tank traps are intact on Sydney’s Northern Beaches.

IMAGE CREDIT: Northern Beaches Council