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Live cam broadcast from the eruption at Meradalir on the Reykanes Peninsula.
The eruption began on August 3rd 2022, 50 Km south of Reykjavík. The eruption’s glowing orange magenta plume is clearly visible from the city on a clear evening. Visiting the volcano requires a two-hour-long hike over uneven ground.
The route is sometimes closed due to poor weather conditions, and children under 12 years of age are not permitted access. All hikers need suitable footwear and clothing.


The Land of Ice and Fire

As the latest eruptions on the Reykanes peninsula dramatically demonstrate, Iceland is a work in progress, where geological processes are continuously destroying and creating. So as the volcano rages at Meradalir engulfs forever terrain formed by eruptions seven thousand years ago, in the adjoining valleys, the brittle, meringue-like lava fields left by last year’s eruptions continue their transformation as they cool, collapsing and eroding. And though no eruption or lava field is identical, we can get a sense of how these fresh eruptions will look. Iceland is a kind of geological time machine, of ’here’s one I prepared earlier’ landscapes. Not far from the new lava fields on the Reykanes peninsula are others that are 300 years, three thousand and 3 million years old. You can travel down a volcano’s chimney into a vast magma chamber, explore a lava tunnel beneath a river of frozen lava, swim geothermal waters in an ancient crater and visit an island village that changed the course of a lava flow to save their harbour.


Location, location, location

Located on on the Mid-Atlantic Ridge, Iceland sits astride the North American and Eurasian tectonic plates and is one of few places where you can see an active spreading ridge on dry land. The plates are moving apart at a speed of about 2 cm per year (about half the speed your fingernails are growing). It’s this widening gap that’s largely responsible for the eruptions every three or four years.

Liberty, Equality, Fraternity... Volcanicity?

Iceland’s volcanic activity occasionally has international consequences. In 2010 ash ejected from Eyjafjallajökull shut international skies for several weeks. More inconvenient still was that time Laki blew its top in 1783. Crops failed, and an ensuing famine killed an estimated quarter of the island’s population and darkened the skies around the world for over a year. The ash cloud led to food shortages and famine in Egypt and France and contributed to the unrest that led to the French Revolution.

A mixed blessing

There are currently over 200 volcanoes in the active zone and at least 30 of these have erupted since the country was settled over a thousand years ago. The big three, Katla, Hekla and Grímsvötn are all overdue an eruption and sit beneath glaciers. Katla sits beneath the vast Mýrdalsjökull glacier and old testament scale floods threaten if there’s a major eruption, so, eh, yeah… that’s a thing.

On the other hand ...

Iceland’s volcanos are a tourist magnate and enable geothermal energy, both factors that contribute greatly to the quality of life in Iceland. Since 2014 geothermal energy has accounted for 66% of Iceland’s primary energy use, with 90% of households heated by geothermal energy. As well as scalding tourists (watch that hot tap/ facet folks), geothermal energy heats swimming pools, greenhouses, fish farms, it even powers snow melting systems for sidewalks, playgrounds and parking space.

Rude awakening

In the small hours of January 23rd 1973, residents of the sleepy island village Heimaey woke to the roaring sound of a fissuring tearing through the centre of their village. Within a day the Westman Islands (Vestmannaeyjar ) population of 5000 was safely evacuated and scientists and geologists arrived to monitor the birth of the Eldfell volcano. The eruption continued for six months, covering much of the island in ash, destroying several hundred homes, and briefly turning the harbour into a boiling cauldron. A successful effort to slow and divert the flow by spraying seawater at the leading edges of the flows. Within a year of the eruption most of the island’s residents returned, and the population had largely recovered. A museum on the Island documents the events and is well with a visit. The Vestmannaeyjar are about a three-hour journey from Reykjavík, with ferries departing from Landeyjahöfn, and Þorlákshöfn.

Lava fields

From soft and mossy to downright spooky-looking knee grazers to barren gravel deserts of fumaroles and steamy vents, Lava fields come in many shapes, sizes and colours and make up some of Iceland’s most haunting and distinct landscapes.

Super fresh

Geologists term lava that’s been cool for less than five hundred years as ‘fresh’, which makes the Lava fields around Fagradalsfjall’s 2021 eruption super-fresh. Over a six-month eruption, Lava travelled up from 20 kilometres beneath the earth’s surface and poured out a series of vents, creating rivers and lava falls that overflowed from one valley to another. Lava was flung as high as 250m raining down in showers of light pumice. All is quiet now. The lava is cooling, (it can take years to fully cool), having formed a dark, elemental new landscape.

Eldhraun - field of dreams

By contrast, the Lava fields created by Eldhraun are positively enchanted. If you’re looking for elves, this is the place (if there’s Elves at Fagradalsfjall, you don’t want to meet them). The soft pillows of Iceland moss feel enchanted. A symbiotic agreement of algae and fungus, the moss is very sensitive to air pollution and grows just one millimetre a year, turning from silvery grey to a vibrant green in the summer months. Moss has been growing over Eldhraun’s massive (565 km2 ) lava field ever since the Laki mega eruption in 1783, softening all trace of Eldhraun’s violent past to create a beautifully serene and calm landscape.


Farther to the north, nearby the towns of Akureyri and Husavík, the Krafla lava fields are a bird of a different feather altogether with bubbling muddy ponds and smoking fumaroles, the ashen lava fields of Krafla demonstrate the wide diversity you’ll find around the island.

Going underground

As a lava stream slows and begins to cool, the first part to harden is the outermost layer, forming a crust around the liquid lava beneath. If the molten lava gets sucked elsewhere, it can sometimes leave behind an this empty crust of lava, et voilà, we have a lava cave or lava tube. There have been about 500 of these discovered in Iceland,and it’s estimated there are thousands more. They are all unique and sometimes offer up some pretty psychedelic geology. Reds from iron, sulphurous yellows from and bluey greens from copper (and all the colours in between) as well as stalagmites, stalactites and other far out formations make for an immersive experience. Several of these are open for tours. Some require a level of fitness and willingness to get a bit mucky, others you can wear you Sunday best, well almost.


Thirty minutes outside Rejkjavil, Þríhnjúkagígur is an extremely accessible as extreme experiences go. Don’t wear your newest sneakers, and a warm coat is advised, but aside from this you’re good to go. Access to the cave is via a small window cleaning elevator that lowers you 120m to a football-field-sized cave. Þríhnjúkagígur is thought to be one of its kind. The cave through which you descend is actually the volcano’s chimney. This vertical cave and magma chamber would normally either be filled with very hard rock or have collapsed in on itself. For some reason at Þríhnjúkagígur, the magma was sucked back out, leaving behind a vast gallery of abstract forms and intense colours drawn from the rock by the intense heat and pressure of the magma.


Another Lava tube in easy striking range of Reykjavik. Leiðarendi was formed when two caves collapsed into each other, leaving behind a circular path of connecting chambers. It’s a good example of an Icelandic lava tube, notable for its diverse and colourful surfaces, some sections are so regular as to appear almost man-made. Access is a little more challenging than Þríhnjúkagígur. You might get a little muddy as you hunch and crawl a bit, but the cave is not too demanding unless you don’t like small spaces, but then caves might not be your thing.


Forty minutes outside Reykjavík, Raufarhólshellir lava cave requires a greater level of fitness and balance. The tour takes on average 3-4 hours to complete with an experienced guide. If you enjoy a physical challenge and want to go deep this might be the tour for you. A highlight, deep inside, is a frozen Lava waterfall. Learn more here about visiting Cave and Lava Tubes.


A distinctive feature of Iceland’s volcanic landscape are the craters and Calderas. There are several craters you can enter, many have small (and not so small) lakes at the bottom, and there’s even one whose azure waters are naturally heated to a perfect swimming pool temperature.

A word on craters

An effusive, shield or fissure-type volcanic eruption occurs when molten magma and gases rise up from an underground magma chamber, travel through a conduit and escape to the surface by forcing a fissure to open up. As the lava erupts, the edges cool and walls build up around it. When the eruption stops, the depression left inside these walls is a crater. Sometimes if the magma chamber beneath is empty, the volcano collapses to expose the magma chamber. This kind of crater, known as a caldera, can be vast and is usually filled with water.

Other craters can be created in a heartbeat by explosive eruptions. Sometimes called Plinian eruptions (after Pliny the younger who witnessed Vesuvius bury Pompeii in CE.79 from across the bay), these occur when pressures from superheated steam and volcanic gasses cause the volcano to pop its top, sending ash and gasses into the atmosphere. These eruptions will often leave dramatic craters behind and cover the terrain with pebble-sized debris.
There are many craters around the Island, below is list of some of the most spectacular and accessible here. For more check out our blog posts.


Kerið is a lake-filled crater an hour east of Reykjavík. Formed 6,500 years ago, the caldera is one of a row of craters called Tjarnarhólar. Much of the terrain here is characterised by an earthy red hue. If the colour seems familiar, that may be because it has long been quarried and exported to Europe where it is used for surfacing roads, where the coloured composite is often used to denote bike lanes and pedestrian streets. Steps have been constructed to take you around the rim of the crater, and down to the lake itself and concerts are sometimes held here, exploiting the unique acoustics of the crater. Earthy reds, rich blacks and the azure lake, combined with the strange acoustics at Kerið, create a memorable immersive experience. Kerið is privately owned, and there is a small charge for entry of 400 ISK The crater is 270 m long, 170 m wide, and 55 m deep.

Fake Hues

A slight word of warning, dear reader, images online are often artificially enhanced, in particular, the colours are saturated. At What’s on we call this fake hues.


Deep in the highlands, among the Dyngjufjöll mountains, the serene landscape of the Askja region was sculpted by large eruptions 12,000 years ago and an explosive Plinian eruption in 1875. The later eruption created a dramatically steep-sided caldera inside the larger one and expelled large amounts of richly coloured ash, or tephra, that gives the region a distinctive palette. Ash from this explosion has been found as far away as Romania. Askja rewards the visitor with spectacular scenery and an opportunity to bathe in the mineral-rich geothermal Lake Viti (hell). Heated to a perfect swimming pool temperature of 25°C ( 77°F), the crater pool is a treat for aching limbs.
Nearby is Öskjuvatn lake, the second deepest in Iceland at 220m. Without a geothermal source, this lake is very cold and not for swimming unless you like it very cold.

Stóra - víti

Another notable caldera crater Krafla is located in the north is Mt. Krafla Stóra-Víti or Big Hell. Rising up where Eurasian and North-American tectonic plates diverge, Krafla and the surrounding region was largely shaped by the intense activity of shield and explosive eruptions, and vast lava flows that occurred in the mid to late 1700s. Paths lead through a geothermal area full of belching, bubbling mud volcanos, fumaroles and steaming vents. A hike around the rim of of Stóra-Víti (big hell) overlooking the azure blue waters is a must. But stay on the marked paths – the earth here can be undermined by geothermal activity, and you don’t want to fall into a superb boiling cauldron of volcanic mud. That this not a lake for swimming; Stóra-Víti or Big Hell is not to be confused with Viti Crater at Askja.

Skútustaðagígar pseudo craters

Just over an hour’s drive east of Akureyri, among the geological treasures around Mývatn lake are the Skútustaðagígar pseudo craters (did you say pseudo craters?) Indeed, these crater-like formations are not and never were directly connected to a magma system. The phoney craters came about caused when thick waves of lava travelled over wet earth. The water beneath expanded like a giant steam engine boiler and demanded more space causing explosions and settling into what we see now. The Skútustaðagígar pseudo craters were formed during the eruption of Lúdentaborgir and Þrengslaborgir around 2,300 years ago.

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