Britain's top extinct volcanoes

It’s been about 60 million years since there was an active volcano in Britain, but there are remnants of their explosive activity in our countryside that you can discover today. What and where are Britain's extinct volcanoes? 


10th January 2018
Glen Coe

Although Britain is not in the Ring of Fire, things were quite different around 60 million years ago.

Today, remnants of the biggest and best volcanoes dot the landscape. You may be surprised to find that you've already hiked on some of them!

1. Cuillin Hills, Isle of Skye
Cuillin Hills
The highest mountain in the Cuillin Range is Sgurr Alasdair at 3,255 ft (992 m) ©Getty

The Cuillin Hills on Skye are considered by many to be the most dramatic mountains in the United Kingdom. If they look fearsome now, imagine what they must have been like at the height of their lava-spewing life in the early Paleogene era, around 65 million years ago.

The Black Cuillin Mountain itself is a particularly awe-inducing sight, making it the most impressive former volcano on these islands.

2. Giant’s Causeway, County Antrim
The Giant's Causeway
The volcanic walkway at Giant's Causeway ©Getty

An UNESCO World Heritage site, the Giant’s Causeway is one of the most beautiful locations in the United Kingdom and one of the most iconic geological relics in the world.

The basalt polygons have fascinated scientists and members of the public for centuries. Legend has it that a County Antrim giant called Fionn was challenged to a fight by his Scottish counterpart Benandonner, so Fionn built the causeway across the sea in order to wrestle his rival. What we see today is all that remains of his bridge. 

3. Snowdon, Gwynedd
Mount Snowdon capped with snow
The mighty Mount Snowdon capped in snow ©Getty

Snowdon mountain in Wales was once at the centre of a furious ring of volcanic activity. One such eruption in the region is believed to have been about three times as explosive as the Krakatoa in Indonesia. That eruption was heard 3,000 miles away and altered global climates and weather for years afterwards. So perhaps before it happened Wales was bathed in sunshine all year round...

4. Ben Nevis, Highland 
View of Ben Nevis from Corpach
The highest volcano in the UK – Ben Nevis ©Getty 

Scotland's highest mountain was also once a large and active volcano. During one extreme eruption in the Carboniferous period it caved in and destroyed itself. All that remained is the collapsed inner dome of the volcano, which we know now as Ben Nevis. Scientists believe the explosion would have been in the same league as Snowdon's eruption. For experienced hikers, here is a way to reach the summit yourself. 

5. Borrowdale hills, Cumbria
The Borrowdales in Cumbria
Nestling in Cumbria are the volcanic Borrowdale hills ©Getty

The Borrowdale hills in the Lake District are of a similar age to those in Snowdonia and were once just as explosive. Another British super-volcano, they have reached the grand age of 450 million years and, despite creating some of England's most stunning landscapes, have long since retired.

6. The Ardnamurchan peninsula, Highland
Sunrise overlooking Loch Shiel from Ardnamurchan
Sunrise overlooking Loch Shiel from the breathtaking Ardnamurchan peninsula ©Getty

The Ardnamurchan peninsula and the Isle of Mull on the west coast of Scotland are remnants of volcanic activity that ended around 55 million years ago but which would have rivalled Iceland's eruptions in their heyday. It might not be immediately obvious on the ground, but looking from the air the concentric rings of the points where lava spluttered up to the surface are clear.

7. Edinburgh, Scotland
Castle Rock at Edinburgh
Two tourist sites in one - Castle Rock and Edinburgh Castle ©Getty

Yes, Edinburgh! The enchanting Scottish capital is home to not one, but two extinct volcanoes. The inventively named Castle Rock, on top of which is perched Edinburgh Castle, is one of them. Arthur’s Seat, the highest point in the city, is the other. Both have been inactive for about 350 million years, so residents of the vibrant city are likely to be safe. 

8. Glen Coe, Highland
Lagangarbh Hut against Glen Coe
Lagangarbh Hut backdropped against Glen Coe ©Getty

Glen Coe is all that is left of an ancient super-volcano, erupting about 420 million years ago. It's considered a classic example of cauldron subsistence. This awe-inspiring part of the Scottish countryside contains the spectacular pyramidal Buachaille Etive Mòr mountain and a steady stream of keen hikers. 

Has all this talk of hills and mountains sparked an urge to get into the countryside? Why not try one of our mountains for beginners?


Main image ©Getty

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