Britain’s best coastal caves, arches and stacks

Along the British coastline you will find a range of dramatic rock formations which range from hidden caves, arches and stacks. Our guide to the most spectacular coastal caves, arches and stacks along the British coast.


Britain is internationally famous for its picturesque coastlines, and much of its beauty can be attributed to the striking edges. Along the coastline you will find a range of dramatic rock formations which range from hidden caves, arches and stacks.


It’s not just about Durdle Door – Scotland is home to the incredible Fingal’s cave, while Wales boasts its Green Bridge of Wales. Here’s our guide to the most stunning caves, arches and stacks around the UK.

How do coastal caves, arches and stacks form?

The destructive force of the lapping waves causes erosion on the headland. When waves find their way into cracks in a cliff erosion is concentrated there, gouging out holes to form caves.

Eventually, the water will erode right through the other side of the rock to create an arch, and in time the top of the arch will collapse under attack from waves and weather.

durdle door
Durdle Door in Dorset is an arch which has not yet collapsed into stacks ©Getty

This will form a stack, a tower of rock separated from the main headland. Later on, erosion will continue to cause the stack to collapse, leaving just a lump of rock at the bottom as an isolated stump.

Sea snail shells on

Best Caves around Britain

Fingal’s Cave – Staffa, Inner Hebrides

Fingal's cave on the Isle of Staffa @GettyImages
Fingal’s cave on the Isle of Staffa, Inner Hebrides, Scotland ©Getty

Tucked away on the island of Staffa off the west coast of Scotland, Fingal’s Cave is filled with impressive basalt columns. This combined with its striking chamber-like interior leaves visitors awe-struck.  The cave has been influential in many works of art, from paintings by Turner to an early Pink Floyd song.

Merlin’s Cave – Tintagel, Cornwall

Merlin’s Cave is located under the crumbling ruins of Tintagel Castle ©Getty

Made famous by Tennyson’s Arthurian poem ‘Idylls of the King’, Merlin’s Cave has long been a location of legend. It’s positioned beneath Tintagel castle, which sits on top of the cliff, and although full at high tide it’s possible to explore the cave when the tide’s out.

Seven Sisters Caves – Broadstairs, Kent

The network of caves winds through the chalk cliffs on the Kent coast ©Getty

This small network of caves is located between Botany Bay and Kingsgate Bay. They’re most famous for their connection to notorious smuggler Joss Snelling, who used to hide his goods in them. Other interesting landforms include an arch and a stack, and of course the white chalk cliffs.

Best Arches around Britain

Green Bridge of Wales – Castlemartin, Pembrokeshire

The Green Bridge of Wales
The Green Bridge of Wales, Castlemartin ©Getty

This rugged limestone arch juts out magnificently into the Celtic sea and is the most famous of Welsh arches. It’s surrounded by Stack Rocks, an impressive collection of stacks and stumps connected underwater to the main headland.

Green Stacks Pinnacle – Flamborough Head, East Yorkshire

An arch at Flamborough Head
An arch at Flamborough Head, Yorkshire ©Getty

Green Stacks Pinnacle is a rocky mound tenuously connected to the headland and boasting a number of impressive features. Perhaps the most eye-catching is its tall narrow arch, making an elegant and surprisingly symmetrical window out to sea.

Bwa Gwyn – Anglesey, North Wales

Anglesey in North Wales ©Getty

 This low-hanging arch has formed in an outcrop of white quartzitic rock. In the past, china clay was quarried from the top of the rock and it’s still possible to see the grindstone used to extract it on top of the rock. A beautiful climb across the cliff tops, but beware of the steep and unstable cliffs.

Best Stacks around Britain

Maiden Stack – Papa Stour, Shetland Islands

Papa Stour is just one of several islands in the Shetlands’ archipelago which boasts fascinating coastal features ©Getty

Papa Stour may be tiny but it’s home to one of the most impressive collections of coastal features in Britain. Maiden Stack is the island’s tallest sea stack, named after the daughter of a Norwegian Lord supposedly imprisoned there for refusing an arranged marriage. The Holl O’ Boardie cave, one of the longest in the world, can also be found on Papa Stour.

Old Harry Rocks – Studland, Dorset

Old Harry Rocks at Studland
Old Harry Rocks at Studland, Dorset ©Getty

These three chalk formations have been affectionately named as Old Harry, Old Harry’s Wife, and No-Man’s Land – which stands slightly further out than the other two. Differing legends suggest the rocks are either named after the devil (nicknamed Old Harry) who is supposed to have slept there, or local pirate Harry Paye.

Marsden Rock – Marsden Bay, Tyne and Wear

Marsden rock stack can be reached on foot at low tide ©Getty

A famous arch which collapsed in 1996, Marsden Rock remains an impressive low-rising stack. At low tide it’s reachable on foot but is entirely surrounded at high tide. If you fancy a drink, head to the top of the cliffs where you’ll find Marsden Grotto, one of the world’s few cave bars.