Durdle Door

Durdle Door is a natural arch of Portland limestone standing in the sea off the Dorset coast near Lulworth, one of the best-known landmarks of the Jurassic Coast World Heritage Site. The arch forms the end of a small headland, the last remnant of a band of hard limestone that once ran parallel to the shore; the waves broke through it, then scoured out the softer rocks behind, leaving a small bay and beach on either side of the headland.

The geology here is unusually clear to read. The rock layers stand almost vertical, squeezed during the mountain-building that raised the Alps, and different bands lie side by side: limestone at the shore, a narrow belt of soft clays and sands, then the thick chalk of the Purbeck Hills. At Swanage, 16 km to the east, the limestone and chalk are more than 3 km apart; at Durdle Door they almost touch. The same hard band, broken into rocks, shows above the waves as Man O'War Rocks in the cove to the east, and to the west as a line of islets called the Bull, the Blind Cow, the Cow and the Calf.

The name is very old. Durdle comes from an Old English word meaning to pierce or bore, and a late 19th-century account described the opening as big enough for a good-sized sailing boat to pass through. The coast is eroding, and in 2013 a large landslip just to the east carried away part of the South West Coast Path, a reminder that the arch is only one moment in a changing landscape. Film crews love it: scenes from Far from the Madding Crowd, Nanny McPhee and Doctor Who, among many others, were shot here.

The arch and the neighbouring Lulworth Cove belong to the Weld family's Lulworth Estate, which keeps them open to the public. A natural cliff path leads down to Durdle Door beach, with steps down to Man O'War beach on the other side.

Getting there

More than 250,000 people a year walk over the chalk hill of Hambury Tout between Lulworth Cove and Durdle Door, the classic approach; for satellite navigation the estate gives the postcode BH20 5PU. The nearest large town is Weymouth, about 13 km away, and the nearest airport is Bournemouth (BOH), about 36 km away.