Dorset is rich in iconic images, but only Durdle Door appears behind the opening titles of the local TV news and indeed in the pages of a UK passport (opposite the Giantâs Causeway). As well as the geological interest of an unusual formation, there is something pleasing about the slightly wonky shape of the rock arch. Watching waves is a mesmerising way to waste time, and the surge of water through the arch on a rough day is impressive and satisfying.
âDurdleâ is from an Old English word meaning âpierceâ, and âDoorâ means just that. The second element is sometimes spelt âDorâ by pretentious writers who presumably think that their inaccuracy makes the name sound more antique and mysterious.
Geologists tell us that the rocks of Durdle Door are 140 million years old, and that it was formed by the action of the waves finding cracks in the vertical limestone beds and creating caves, which eventually collapsed together to form the arch. The coast hereabouts is subject to erosion and the geologists also tell us that at some point it will collapse, leaving just a limestone stack similar to those like the Bull and the Cow, which are strung out to the west, or a reef as in Man oâWar Bay to the east. They just canât tell us in which century it is going to happen. â