Take a walk back into our volcanic past

Journey through the British Isles with this unique guide to nine walks that take you to the heart of our volcanic origins

INSPIRED BY BBC2’S LIVE introduction volcano live introduction contents glossary england volcanoes? The phrases and Hadrian’s Wall 4 descriptions you Side Pike 6 right here! need to know Magma Rocks of the Snowdon 8 they’re not about to erupt any time soon, Earth’s crust and/or Llanddwyn Island 10 says Professor , but our mantle (the layer between Our Active Land 12 ancient volcanoes offer clues to the the crust and the core) that have melted or earth-shattering past of the british isles Arthur’s Seat 14 semi-melted Ben Nevis 16 wonder and peril that make Pyroclastic eruption Talisker Bay 18 volcanoes the most thrilling A violent eruption where natural phenomena on Earth. the magma is blasted out as fragments, rather than The Giant’s Causeway 20 But live volcanoes are also flowing out as Portrush Rocks 22 windows into our planet. Whatever your perspective, Pyroclastic flow The history of the they are places where you can The hottest, most violent world — in a year 24 olcano Live on BBC2 really sense that the Earth type of pyroclastic eruption

celebrates the seething beneath your feet is shifting Caldera A large V molten world of active — places that make you think depression (about 15km volcanoes, which have got to very differently about the long and 10km wide) be some of the most exciting world around you. created during a The walks have been places on the planet. In the UK, of course, we pyroclastic flow eruption written by Dr Kathryn For a start, their barren have no active volcanoes. Goodenough of the British Sill Magma that doesn’t rocky wastelands look like They occur at the edge of the Geological Survey, Dr Mark reach the surface, but another planet. The sights, tectonic plates that make up Cooper of the Geological cools down when smells and sounds, too, are the surface of the Earth and ancient edifices centres erupted colossal country. One of the best places Church Stretton in the Survey of Northern squeezed between layers alien, from superheated at the moment — indeed for A view of the lakes of Glaslyn quantities of magma. to see that is . Welsh borderland are Ireland, Clair Drew, who of the bedrock. This is gurgling mud pools to noxious the next few million years — and Llydaw from near the Over millions of years, the Clamber up to the top of the outpourings of leads guided walks along summit of Snowdown known as “intrusive” rock gases. Menacing craters burst we remain some distance spreading of the Atlantic Arthur’s Seat and you can 600-million-year-old . Hadrian’s Wall, and Paul Igneous Any rock into action with fiery showers from any plate boundaries. seaway has shunted eastward see isolated rocky pinnacles Gannon, a science and formed from cooled of incandescent magma or those volcanic centres — scattered along the Forth lthough lacking the technology writer and magma, whether streams of molten lava. he last hurrah of the Arran, Mull, Skye — away from estuary, each the eroded fireworks of live author of guidebooks intrusive or erupted Some eruptions are so big British volcano was the well of superheated rock neck of a former volcano. volcanoes, our volcanic A Basalt Rock formed on the geology of that they drive plumes of hot about 60 million years “In the UK, you that originally fed them, so The jagged peaks of heritage, fashioned by Britain’s hills. T from magma that usually rock and ash high into the ago, when an extraordinary that, today, that upwelling Snowdonia and the Lake millions of years of erosion, Please note: maps do not walk on flows easily to form lavas atmosphere, playing havoc fiery outburst accompanied now feeds the craters and District are even older reveals the inner workings of are illustrative and Subduction zone with global aviation and the wrenching open of the volcanoes, you geysers of Iceland. volcanic edifices, while Ben these natural furnaces. not to scale. The area where an spawning lethal clouds of North Atlantic Ocean. The UK’s volcanic fires may Nevis is the disembowelled For, as the following pages walk within them” oceanic plate “subducts” scalding debris that obliterate All along what is now be no more, but remnants of remains of a massive show, in the UK you do not Cover IMAGE: Getty prof iain stewart below a continental plate, anything in their path. the western shores of an enduring eruptive past collapsed volcano. Even walk on volcanoes, you walk Art direction and map leading to volcanic activity illustration: Jacob Howard It is that mix of natural Scotland, huge volcanic can be found throughout the the gentle summits above within them. alamy 2 3 volcano live England volcano live england

& the Great Whin Sill, roman road The route of Hadrian’s Wall Hadrian’s Wall northumberland follows the geological line of the Great Whin Sill hike the roman way across our volcanic past

adrian’s Wall is an iconic Hadrian’s historical monument, Wall FACT FILE H hugging the natural features from one side of the Highshield island to the other. Winshield Crags Housesteads The central section of the Crags Wall is the most impressive, incorporating natural defences formed by the steep face of Cawfield an undulating line of hills. Crags These hills are the product of volcanic activity under the land surface about 300 million years ago. The Earth’s internal convection currents caused A bus service from Carlisle WALK Hadrian chose the narrowest the underlying tectonic plate takes 40 minutes. duration 3 hours route across northern England to stretch, crack and thin. Vast Walk north up to the ridge, Distance 6–7 miles (10k) for his 73 mile-long wall, which quantities of molten magma skirting the eastern side of Grade Moderate to ran from Wallsend on Tyne in the started to rise up. But rather the fort to reach the Wall. hilly terrain east to SolwayF irth in the west. than erupting onto the The walk finishes at the Map OS Explorer OL 43 In choosing the route he surface, the magma was Cawfield Quarry car park. To consciously used the geology squeezed between layers of catch the AD122 bus back to it hugs the top of the sill to of the landscape and the natural existing rock and cooled down Housesteads, follow the road Highshield Crags. At the defences provided by the crags there, forming large south to the Milecastle Inn on western end a good example that mark the outcrop of the horizontal sheets called sills. the B6318. In places the walk of columnar jointing can Whin Sill. The Great Whin Sill, on can be slippery, so suitable be seen. This prominent The Sill has been quarried which the Wall stands, is the clothing and footwear are feature of the Great Whin since Roman times and today, largest of the swarm of sills recommended. Sill is common in igneous many of the disused quarries that help define the landscape rocks and results from the have become places that of northern England. FEATURES TO way the magma cools and harbour wildlife and rare plants. Where to start LOOK OUT FOR contracts slightly, producing Start off from the car park Take the western path vertical cracks. columnar jointing can be seen of Housesteads Fort, near following the Wall up the Continue along the ridge, here together with vesicles, Haydon Bridge, Hexham. gentle rise of Housesteads over Winshield Crags, which mineral-filled cavities formed Today it’s an English Heritage Crags. The steep angle of the is the highest point at 345m, by gas bubbles trapped in the site but 1,800 years ago it was scarp slope of the sill is very before finally descending molten rock. They are usually

home to 800 Roman soldiers. impressive. Follow the Wall as into Cawfield Quarry. More no larger than a penny coin. pa getty; 4 5 volcano live England volcano live england

Side Pike Langdale, Lake District enjoy a landscape loved by walkers and created by violent eruptions

he head of Langdale is Old great one of England’s finest Dungeon Langdale other places Ghyll T mountain landscapes. NT The knobbly fells that campsite of interest surround the dale are the product of violent eruptions Side Pike that occurred in the same Lingmoor subduction zone that affected Tarn Snowdonia (see p8). But while those eruptions happened under the sea, Blea Tarn in the Lakes they took place on land. Massive lava flows were High Rigg, Keswick followed by explosive Views of lava flows FEATURES TO WALK stacked on top of one pyroclastic eruptions from 1 LOOK OUT FOR Duration Short walk 2 /2 fissure vents, forming various another from St John’s in The first few rock outcrops hours; long walk 5 hours plus types of a rock known as tuff. the Vale and from summit. are welded tuffs — created in Distance Short walk These eruptions also the very hottest type of 2m (3k); long walk 5m (8k) Sough Top, Peak created large depressions or pyroclastic eruption and Grade Short walk moderate; District Lavas and calderas, which rapidly filled distinguishable by the thin long walk hard pyroclastic rocks form a with rainwater, turning them streaks of flattened lumps of Map OS Explorer OL 6 convoluted line of grassy into lakes (though not the pumice ripped away by the hills rising above this part same lakes as today, which eruption of an incandescent coarse tuffs with visible of the White Peak. are of more recent origin). cloud of burning gas and lumps, then bedded and The Wrekin, near Where to start molten fragments of magma faulted sedimentary tuffs, Chester Layers of lava Start at the bus stop/car park and rock. This is the type of followed by more lavas. erupted over 650 million at Old Dungeon Ghyll and walk eruption responsible for The walk to the summit years ago — some of (via the NT campsite) up to creating calderas. and back takes less than two England’s oldest rocks — the pass between Great The rocks on Side Pike hours, but can be extended form this distinctive hill. derive from a collapse down over Lingmoor Fell (by looping Langdale and Little Langdale. Caer Caradoc, near one of the steep sides of an around the southern flank of Pick up the track on the left Church Stretton Side Pike — do not descend that goes through a gate and ancient caldera and have Pyroclastic eruptions and direct towards Lingmoor Fell) rises up Side Pike’s western become all mixed up. lava flows produced the rock of ages Volcanic landscape of flank. Suitable footwear and As you ascend further you with several more rock types lumpy rocks of this fine clothing are essential. pass a mix of volcanic rocks to be seen (allow 5 hours plus), the lava crag of Side Pike ancient hill fort. as seen from Lingmoor Fell

— lavas come next, then returning along Langdale. alamy getty; 6 7 volcano live wales volcano live wales

tuff territory Pyroclastic tuffs (rocks) Snowdon gwynedd are scattered beneath the looming peak of Snowdon today’s mountains were once on the edge of a continent

nowdon and its surrounding mountains S are among the most fact file graphic examples of ancient Pen Y PAss volcanic landscapes. Miner’s Track Some 450 million years ago the chunk of tectonic plate that is today North Wales was Snowdon Glaslyn summit Llyn on the edge of a continent Llydaw facing a major ocean. The plates underlying the ocean and the continent were driven into one another by the Though now 1,085m (3,560ft) Earth’s internal convection above sea level, proof that currents, causing the oceanic WALK FEATURES TO Snowdon’s origins lie beneath plate to subduct underneath Duration The shorter route LOOK OUT FOR a sub-tropical sea come in the the continental plate. is 2–3 hours; the route to the All around the Miner’s Track shape of the fossilised shell This led to a series of summit about 5–6 hours masses of tuffs can be seen, fragments that can be found undersea eruptions extending Distance 5 miles (8k) rocks formed from the near the summit. over a period of about ten 1 or 8 /2 miles (14k) fragments thrown out in a These marine animals, known million years. There were Grade The shorter route as brachiopods, would have been great outpourings of lava, pyroclastic eruption. As you easy; longer one hard encased in hot ash from other but also several massive approach the first lake, Llyn MAP OS Explorer OL 17 volcanoes and, having fossilised pyroclastic eruptions. Teryn, you can see regular on the sea bed, were brought to In these eruptions the columnar jointing in the rock the surface in the activity that molten magma exploded in where to start headland holding in the lake. saw the creation of Snowdon. violent clouds of incandescent Start from the car park/bus This is the same feature seen fragments rushing across the stop at Pen y Pass and at Giant’s Causeway (see p20), ground and into the sea. take the route to the caused by the way in which from light to dark. The darker These eruptions produced summit following the initially molten magma cools down. rocks come from a different the rocks of Snowdonia. easy Miner’s Track. Continue up to the highest magma type and are lava There’s limited parking lake, Glaslyn, where you can flows as well as tuffs. available at Pen y Pass, but either turn back or continue You can find proof that there is a bus service that up a steep stony track to join these eruptions took place runs from the park-and-ride the Pyg Track and the route undersea from just below the at Nant Peris and Llanberis. to the summit. summit trig point where shell Proper clothing and Just before joining the Pyg fossils can be found in the

footwear are essential. Track the rocks change colour rocks. Return by the Pyg Track. alamy 8 9 volcano live wales volcano live wales

Llanddwyn Island Anglesey the perfect place to see the effect of tectonic plate movement

small tidal island on the south-western tip other places A of Anglesey may seem Newborough an odd place to seek out rocks of interest with extremely violent origins on the ocean bed. But, some 600 million years ago, the earth’s inner convection currents caused an oceanic Newborough plate to be stretched. Volcanic Warren eruptions took place that created new sections of Llanddwyn Conwy Mountain, oceanic plate, which in turn Island near Conwy spread outwards, leaving Not so much a mountain, space for yet more plate to where to start WALK more a little hill at the be created. From Newborough village, Duration 2 hours northern tip of This spreading plate then 1 follow the signed route to Distance 2 /2miles (4k) Snowdonia. Some of the collided with a continental the Newborough Warren Grade Easy earliest volcanic eruptions plate and was forced beach car park. Walk down MAP OS Explorer 263 created lumpy “breccia” underneath it, recycling the rocks found here. ocean bed rocks back into to the beach and follow it to of the obvious steps you find the earth’s mantle. the link with the island. Check a rock full of lumps. This was Cadair Idris, near But a small chunk of the tide times before crossing. created by an earlier phase of Machynlleth oceanic plate escaped this FEATURES TO the volcanic eruptions, when Pillow lavas, tuffs, fate and in the frenzy was LOOK OUT FOR columnar jointing and ripped off, getting caught up magma reacted angrily with Approaching the tidal link to other features can be on the edge of the continental the seawater, causing the the island you meet several magma to fragment. seen on this impressive plate (in what’s known as an mountain at the southern green-coloured rock outcrops. Climb the steps and walk to accretionary zone). end of Snowdonia. This rescued chunk of From some angles these the end of the island. Go down outcrops can be seen to to the little bay to the west of ancient oceanic bed now Strumble Head, fragmented past consist of rounded lumps. the smaller lighthouse and in The view from Llanddwyn appears on the surface on near Fishguard Known as pillow lava, this is the rocky cove to the right, Island towards the volcanic Llanddwyn Island. A fine display of pillow formed when packets of lava encounter a mixture of hills of Snowdon lava, originally erupted on burst through the ocean floor striking rock types, including the sea floor, forms the and cool down quickly. If the lava, tightly packed into a spectacular coastal tide permits, cross to the “mélange” in the violence scenery in this area.

island. Below and to the right of the subduction zone. alamy getty; 10 11 VOLCANO live our active land the history of volcanic activity in the uk is as thrilling as anything you’d expect to find in hawaii or iceland…

Map Key Intrusive (Magma that intrudes rock, but is never exposed to the air) Extrusive Arthur’s Seat, (Magma erupted as lava) Edinburgh (363m yEARS) Major lava field Arthur’s Seat is a plug (an area where (more than 2km thick) magma has hardened in the vent of a previously active volcano). In fact much of Scotland’s Midland Valley is occupied with lava and ashes, and Ardnamurchan (55M YEARS) would once have been similar to what we see today in the East African Rift The enchanting volcanic landscape of Valley. However, magma does not Ardnamurchan, with its striking concentric always make it to the surface. It rings of hills, was formed some 55 million can intrude into rock both vertically years ago. The rings were formed by molten (as dykes) and horizontally (as sills), magma, which didn’t get all the way to the as seen at the Salisbury Crags, surface, cooling and solidifying in concentric baking the rock either side of it. cone-shaped sheets. Since then erosion has There are numerous swarms of removed several thousand metres of dykes in the Highlands. material to reveal the roots of the volcano.

Dyke Swarms (58m Years) Younger swarms of dykes can be seen throughout the country, formed by stresses with the early opening of the North Atlantic. The Cleveland Dyke is derived from a magma chamber on Mull and is likely to have been emplaced in a single pulse in a matter of days. It can be traced for 400km from Mull to Durham.

Snowdonia and the Lake District (500m years) Here volcanic deposits are thousands of metres thick, formed after eruptions from ancient volcanic island arcs (as seen today in the Lesser Antilles). There is also evidence of rare submarine lava (termed pillow lava) as well as old Violent volcanic activity, calderas and vents. Northern Ireland (65m years) Activity broke out over a hot spot, as seen in Hawaii, due to the opening of the North Atlantic Ocean (still Mantle plumes beneath widening today at about 4cm a year, and pulling South-west England (275m years) Iceland apart). Lavas are found on the sea bed A large rock, formed from cooled magma deep in across to Northern Ireland, where they form the the Earth’s crust — known as a – has Giant’s Causeway. The hexagonal basalt columns become exposed due to erosion, and can be seen on are also found at Fingal’s Cave, on the Isle of Staffa, Dartmoor and at Land’s End. In fact, the granite off Mull. The columns result from the perfect cooling stretches all the way to the Isles of Scilly. Similar of basaltic lava, and are similar to those seen in examples can be found at Yosemite, as part of the lavas erupted from fissures in Iceland. Sierra Nevada Batholith. volcano live scotland volcano live scotland

Arthur’s seat edinburgh follow the remains of an ancient volcano in the heart of the city

cotland’s capital is built Edinburgh on seven hills, which tell S the story of the city’s fact file volcanic past. The hill of Arthur’s Seat is all that remains of a volcano that last The Radical erupted some 340 million Road years ago. At that time, central Scotland was part of a larger continent and lay Arthur’s close to the Equator, with Seat low hills and shallow lagoons that were covered by tropical vegetation. The Arthur’s Seat volcano WHERE TO START WALK mainly erupted flows of lava Parking is available at Duration: 2–3 hours The path to the top of Arthur’s that spread out northwards, 1 1 Holyrood Palace, which can Distance: 2 /4m (3 /2k) Seat was named the Radical but from time to time, also be easily reached on foot Grade Easy to moderate Road because of the actions explosive eruptions produced from the city centre. Good Map OS Explorer 350 of striking artisans in 1820 that clouds of volcanic ash. Some shoes are needed as some became known as the Radical magma (molten rock) rising of modern geology”. It was of the paths are rough, and War. At the suggestion of Walter up beneath the volcano on the Radical Road that he Scott, unemployed weavers were never made it to the surface; a warm top or waterproof realised, over 200 years ago, given the job of making the route Salisbury Crags is a sill, may come in useful. that the rocks in the cliffs navigable by foot and hence it formed when a thick sheet of From the Palace, take the had once been molten, and acquired its name. Talking of magma cooled and solidified steep path known as the that the hills around him roads, Edinburgh’s streets were underground. These hard Radical Road, a well-trodden were formed by ancient once covered with cobbles igneous rocks have remained route that climbs up volcanic activity. mined by quarrymen from the as the softer rocks around underneath Salisbury Crags, From the end of the hard rocks of Salisbury Crags. them have eroded. then continue up the path, Radical Road, the path which has quite steep ascends over rubbly-looking sections, to Arthur’s Seat. rocks, made up of many a mini version of Giant’s volcanic fragments all Causeway (see p20). FEATURES TO jumbled together, which Descend northwards down city peak LOOK OUT FOR formed in the core of the the long valley from the Towering over the skyline, The path follows in the volcano. The summit, with summit, with the lavas of Arthur’s Seat is the iconic footsteps of the great James its fantastic views, is made Whinny Hill on your right, legacy of a volcano that erupted 340 million years ago

Hutton, known as the “father up of columnar basalts, like to return to the Palace. alamy 14 15 volcano live scotland volcano live scotland

ancient heights The summit of Ben Nevis, Ben Nevis highland sculpted by violent volcanic episodes more than the uk’s highest mountain grew where continents collided 400 million years ago

en Nevis is well known Fort William as the UK’s highest B mountain, but it is also fact file one of our most fascinating ancient volcanoes. Lochan Meall The precursors of the an t-Suidhe Scottish Highlands — the Caledonian mountains — were Achintee formed between 470 and 430 House million years ago, thrown up by the forces associated with Ben Nevis continents colliding. At great depths beneath these mountains, rocks were The summit of Ben Nevis — melted to form magma, which FEATURES TO WALK 1,344m (4,409ft) above sea level then moved upwards until it LOOK OUT FOR Duration 5–8 hours — still features the remains of was finally erupted from This path climbs steadily over Distance Just over an observatory built in 1883 and volcanoes. Several such 1 reddish granite rocks, formed 9m (14 /2k) permanently staffed until lack volcanoes existed, but the when magma cooled and Grade hard of funding forced its closure in most dramatic were those of crystallised in a magma Map OS Explorer 392 1904. The weather information Glencoe and Ben Nevis. chamber deep beneath the collected during this period is Some of their eruptions volcano. Taking a closer summit have now been still said to be the most were enormously explosive, look at the rock, you might shattered by frost into many comprehensive set of data producing pyroclastic flows large blocks, they were on mountain weather recorded and clouds of volcanic ash. be able to see the individual minerals that crystallised originally formed as lava in Great Britain. Prior to its establishment, from the magma. flows, moving down the WHERE TO START meteorologist Clement Wragge After passing a small loch, slopes of an active volcano Good boots, warm and made daily treks to the summit Lochan Meall an t-Suidhe, the over 400 million years ago. waterproof clothing, food and — setting out at 5am — to take path up Ben Nevis begins to These rocks are andesite drink, and a map and compass weather measurements. Today, zig-zag. The lower zig-zags lavas — named after the are all essential. This walk a small emergency shelter sits are still in granite, but higher Andes, where similar lavas starts from Achintee, about on top of the observatory tower, 1 up there is a distinct change; are formed in modern-day 2k (1 /4m) outside Fort William. making it the highest man-made volcanic eruptions. Parking is available at the summit and upper structure in the UK. Achintee and the nearest slopes of Ben Nevis are made On the North Face, rail station is in Fort William. up of rocks that were formed evidence for pyroclastic flows The ascent and descent in volcanic eruptions. and enormous explosive

are by the same route. Although the rocks on the eruptions has been found. pa getty; 16 17 volcano live scotland volcano live scotland

Talisker BayIsle of Skye walk where the north atlantic opened and mountains rose

round 60 million years ago, a chain of other places A volcanoes developed in western Britain as the North of interest Atlantic Ocean began to open. Bidean nam Bean, The Isle of Skye is one of Glencoe Climb up the most dramatic places to through pyroclastic rocks see the volcanic rocks that and lavas of the “secret were formed at that time. The Talisker valley” to the summit, peaks of the Cuillin mountain then descend over Talisker range are made up of rocks Bay columnar jointed crags on from the magma chamber the way down from Stob deep beneath the volcano, Coire nan Lochan. while the northern peninsulas Ben Hiant, of the island are made up of low tide so that you can visit WALK Ardnamurchan thick piles of lava formed the sea stack. Duration 2 hours, but can be An easy climb over lavas during repeated eruptions. extended if you want to spend and intrusive rocks and When the volcanoes FEATURES TO a day at the beach — the icing on the cake — Distance 2–3m (3—5k) there were erupting, Skye would LOOK OUT FOR superb views of the have looked much as parts and back From the end of the road Ardnamurchan “volcanic of Iceland do now, and many Grade Easy through Gleann Oraid, west Map OS Explorer 411 ring complex” with its of the same volcanic features of Carbost, the walk follows circular ring of hills. can be seen. a track past Talisker House One of the most pick your way over boulders spectacular places to study and down to the shores of to the sea stack at the Skye’s volcanic past is at Talisker Bay. southern side of the bay. Talisker Bay, on the west coast. The bay is framed by The rock platform around towering cliffs, built up of this sea stack preserves WHERE TO START a succession of lava flows, volcanic features that are as To reach Talisker Bay, take each one no more than a few clear today as when they the A863 from the Sligachan metres thick. The sheer scale formed 60 million years ago Hotel and turn off to Carbost, of this lava pile shows that — including ropy lava surfaces, Dumbarton Rock then follow the single-track Skye was once home to a rounded holes where gas Once a volcanic plug, dark road down Gleann Oraid to long-lived volcano that bubbles were trapped as basalt with columnar Talisker. There is parking for erupted periodically — just as the lava cooled, and reddened jointing can be seen well dramatic edge a few cars at the road end. Icelandic volcanoes do today. tops that formed as the lava from Castle Road at the Lava produced by successive eastern end of the rock. eruptions 60 million years ago It is worthwhile consulting This walk is best done at “rusted” where it was exposed produced Talisker Bay’s cliffs

the tide tables and going at low tide, when it is possible to to the air. alamy 18 19 volcano live NORTHERN IRELAND volcano live NORTHERN IRELAND county The Giant’s causeway antrim escape to an unforgettable landscape of sea and rock

he Giant’s Causeway sits on the spectacular Port Reostan fact file T north coast of . Legend has it that the Irish giant Finn McCool built Grand the causeway in order to fight Great Causeway Port Stookan his Scottish counterpart, Noffer Benandonner. The scientific story is that Shepherd’s Declared a World Heritage site the Giant’s Causeway and path entire Antrim Plateau were Weir’s by Unesco in 1986, the Giant’s Snout spewed onto the land as Causeway is thought to consist lava flows from fissures of more than 40,000 interlocking Causeway Centre that appeared here about basalt columns, some up to 40ft in height. But it’s not just the 60 million years ago when the FEATURES TO WALK North Atlantic started to open. upright stacks that feed into the LOOK OUT FOR duration 2–3 hours. mythology — other features like These rocks are the largest 1 Head down the hill towards Distance 2 /2m (4k) onshore remnants of such the Giant’s Eyes (pictured) add to the Great Stookan headland. Grade Moderate to hard. volcanic activity in the UK and the story. Their appearance is On rounding Weir’s Snout the Suitable for children have been the focus of much created by cores of basalt that Giant’s Causeway will come Map OSNI Discoverer, scientific controversy and survived tropical weathering. into view. In the distance you’ll Sheet 5 advance during the past two decades. see what look like chimney tops — these are columns the path here. The Grand watched by Giant’s Eyes (see Causeway is next to explore above), which occur in the Where to start made of the same basalt that and, like the others, is made orange-coloured layer. The Parking, facilities and toilets forms the rest of the causeway. are available at the new A layer of orange rock is up of hexagonal columns that wall-like structure that cuts National Trust visitors’ centre, also visible and separates the formed as the hot lava cooled, up through the lava flows 44 Causeway Road, Bushmills headland into a lower and contracted and cracked. here is known as a dyke, BT57 8SU. Start by looking upper series of horizontal In the centre of Port Noffer which formed as molten rock around the visitors’ centre. layers, which are solidified bay try the Giant’s Boot for was trapped as it travelled Sturdy footwear and care will lava flows. size, and then walk onwards towards the surface. be required on wet or loose Follow the coastal path to the Giant’s Pipe Organ, a Return the way you came, rock surfaces and near cliff round Port Ganny as far as the fine example of columns that but turn left up the Shepherd’s edges. Check the weather cluster of very large boulders display both a colonnade and Path to the cliff top and follow no myth forecast and dress — the Giant’s Marbles! The entablature. Continue, but the signs back to the visitors’ Hexagonal columns that appropriately. Little and Middle Causeways just before Port Reostan you centre. Stop at Aird Snout for form the Giant’s Causeway and the Giant’s Marbles

are immediately to the left of might feel you are being a fine aerial view. alamy 20 21 volcano live NORTHERN IRELAND volcano live NORTHERN IRELAND

PoRtrush Rocks county antrim fossils found here changed the very nature of volcanic studies

ortrush is located Skerries as dolerite and gabbro. about 6m (10km) west Ramore Walk past the playground P of the Giant’s Causeway. Head and follow the path to the cliff Ramore Head and the chain that forms the south-western of small islands just off the side of Ramore Head — at coast, called the Skerries, Visitors’ centre some 30m high you’ll need to keep hold of your hats. Look are all that remain of a Portrush Harbour 60-million-year-old body of strand back again at the Skerries and volcanic rock, known as a it should become apparent sill, which was injected into that you are standing on a 200-million-year-old saucer-shaped sill. Jurassic rocks. Continue the walk It was here that a battle southeast to Portrush Portrush raged between two opposing Harbour, then follow Ramore groups of geologists from WALK shape of coiled fossils known Street and Ramore Avenue 1775 until around 1800; the back to the visitors’ centre. Duration 2–3 hours as ammonites. The remains of Neptunists, who believed all 1 For more geology, take a short Distance 1 /4–3m (2–5k) these marine creatures occur rocks precipitated from sea drive to White Rocks and Grade Moderate in rocks that the Neptunists water, versus the Plutonists, examine the volcanic vents Map OSNI Discoverer, Sheet 4 believed were basalt — their who proposed that some found at the eastern end of theory being that if basalt had rocks were formed from Portrush strand. and near cliff edges. Check formed from molten lava then molten rock (magma) and the weather forecast and how could life have survived volcanoes. Careful field dress appropriately. The walk within it. The Plutonists observations made here by other places is not tide-dependent but you the Plutonists overturned the showed the fossil-bearing will be able to see more on of interest Neptunist theory and shaped rocks not to be basalt, but a falling tide. the modern understanding marine sediments that had of . been baked by the injection Features to of molten rock nearby. Where to Start look out for Continue northwest past Start at the Coastal Zone From the observation area of the old lifeboat station and Northern Ireland Environment the excellent Coastal Zone, look at the rocks that form Agency visitors’ centre in Bath look out to sea at the Skerries the foreshore here. They are Scrabo Country Park, Newtownards, Road, Portrush. There are and notice how they dip into also dark grey but with a stacking up County Down Volcanic parking spaces and toilets at the inner bay. Immediately coarse sugary appearance White Rocks, a sea stack to dykes and sills can be the centre. Sturdy footwear northwest, on flat-lying, dark (crystalline). These are the east of Portrush, made seen to cut through and care will be required on grey rock surfaces, you will igneous rocks that cooled of white chalk with large wet or loose rock surfaces older red sandstones. blocks of volcanic basalt find signs of ancient life in the from magma and are known alamy 22 23 VOLCANO live

The three Volcano Live presenters 4.6 BILLION YEARs of describe their favourite UK earth — in one year 1 January Formation of the Earth geological hot spots 4 March First bacteria appeared 19 November No Atlantic Ocean, England and Scotland located on different continental plates 22 November Volcanic activity in North Wales and Lake District 2 December The first tree-like plants appear 6 December Volcanic activity Iain Stewart in Scotland For me, as a west of Scotland lad, my The Giant’s Causeway in Northern 8 December Creation of first and personal favourite home-grown volcanic Ireland is one of the most surreal only supercontinent, Pangaea, landscape is the Campsie Fells that landscapes that I can think of. It has which is mostly desert overlook Glasgow. They are a magnificent such mystical and mythological staircase of layered lava flows that associations, but is of course an 10 December Mountain-building spewed out of the same magma-fuelled intriguing geological wonder. I think in Europe, leading to mantle maelstrom that created the more famous the fact of it being on the coast helps plumes beneath SW England rocky skyline of Edinburgh 50 miles or so make it a unique and magical place. 12 December Mass extinction to the east. It’s one of the hidden gems event; 95 per cent of species die: of the Scottish landscape. no definitive explanation 14 December First dinosaurs 25 December Opening of North Atlantic 26 December Dinosaurs become extinct. The UK moves north, to present position (moving 1,100km/ 685m in 60 million years) 27 December Violent volcanic activity in western Scotland For more information and Northern Ireland As a comedian, Edinburgh is a place I’ve Learn more about Volcano Live: 29 December Collision of India seen a lot of and I’ve climbed Arthur’s www..co.uk/volcanolive with Asia, forming the Himalayas Seat many, many times. Last year I think The British Geological Survey: I went up it about five times. It is rare to www.bgs.ac.uk/discoveringGeology 31 December Arctic ice-cap forms be in a capital city where you can have The Natural History Museum: 31 December, 23:25:00 Origin a walk like that. Geologically it is really www.nhm.ac.uk/nature-online/earth of Homo sapiens in interesting — it may have been a volcano, Scottish Natural Heritage: 31 December, 23:57:14 Arrival but you can also see evidence of www.snh.gov.uk/about-scotlands- of modern man in Europe getty glaciers there. nature/rocks-soils-and-landforms/