Old Man of Hoy

The Old Man of Hoy is a sea stack of red Old Red Sandstone standing about 137 meters tall off the coast of the island of Hoy in Orkney, Scotland. It formed as wave erosion progressively attacked a headland of horizontally bedded sandstone resting on a more resistant volcanic base, eventually cutting through the neck of the headland and isolating the stack from the cliff behind it. The stack is thought to be a geologically young feature, likely having formed within only the last few hundred years, and erosion continues to undercut its base today, meaning it will eventually collapse. It has been a notable rock-climbing destination since its first ascent in 1966 and is one of the tallest sea stacks in Britain.