Durdle Door is a natural limestone arch near Lulworth Cove and one of the most photographed landmarks on the Jurassic Coast.
On this stretch of concordant coastline (where bands of rock run parallel to the shore) the rock strata has been folded until it is nearly vertical. Closest to the sea is a band of tough Portland limestone. Behind it is a band of weaker rocks that are easily eroded, and behind them is a stronger and much thicker band of chalk.
This geology is responsible for a number of well-known natural features including Lulworth Cove itself. At Durdle Bay all but a very short stretch of the limestone has been weathered away, leaving only a small headland. Durdle Door is a natural arch at the western end of this headland.
The name comes from the old English 'thirl', meaning 'bore' or 'drill'. Remnants of other arches can be seen up and down the coast in the form of stacks and stumps. Teams are working to halt the progress of erosion on Durdle Door itself, preserving it for future generations.
On each side of the arch lie sweeping shingle beaches which are popular with tourists in summer.
The closest village is Wool. There is a pay and display car park accessed via Durdle Door holiday park and a short walk down some steep steps to the beach.
Alternatively, Durdle Door is about 1km west of Lulworth Cove along the coast path. Don't expect a quiet stroll along the cliffs though. The stretch of footpath between Durdle Door and Lulworth Cove is the busiest in the south west and sees more than two hundred thousand walkers every year.