Twelve Apostles

From the main clifftop boardwalk, the first sight is almost theatrical: a line of pale limestone towers stands offshore in the crashing surf, their silhouettes sharp against an open sky, as if the continent simply drops away into the infinite blue of the Southern Ocean.

The scale surprises even visitors who have seen photographs: the tallest stacks reach 50 metres, yet look slender against the enormous sky — it is only when a wave breaks against their base and you realise the surf reaches halfway up the rock that the ocean's power becomes tangible.

The light changes with astonishing speed; a cloud shadow can turn the pale limestone briefly grey, then a break in the clouds sends warm gold across the water. Photographers return at different hours not to find a better angle but to watch the same stacks perform differently under changing light.

They are among the most visually dramatic coastal formations in Australia — wind-and-wave-carved limestone towers that have become the iconic image of the Great Ocean Road and one of the most photographed natural landmarks in the country.

Despite the name, there have never been twelve stacks — only nine existed at most, formed from Port Campbell Limestone deposited 15 to 5 million years ago, making them a window into geological time that is vanishing before your eyes as the Southern Ocean continues its slow erosion.

Two stacks have collapsed in recent memory — July 2005 and 2009 — leaving seven standing today, and the process of erosion is ongoing; each visit captures the stacks in a slightly different state, giving the place a poignancy that more static landmarks lack.