Fortunately, it is a shield volcano
France | La Réunion | Anno 2023
Friday 20 October | Sud Sauvage – Grand Brûlé
Saturday 21 October | Grand Bassin – Route du Volcan – Piton de la Fournaise
Friday 20 October | Sud Sauvage – Grand Brûlé
La Diagonale des Fous. The name says it all. The course of this race runs diagonally across the island, and you have to be a little crazy to take part. Yet it’s the biggest annual event on La Réunion. This year, no fewer than 2,800 ultra-runners are participating.
You have to be a little crazy to take part. Yet it’s the biggest annual event on La Réunion
Last night at nine o’clock, they set off from Saint-Pierre on the southern coast. Destination: Saint-Denis on the northern coast. It’s a gruelling course that cuts through two of La Réunion’s three cirques. That means they have to climb the steep rim of such a volcanic amphitheatre three times – and descend again on the other side. That adds up to more than 10,000 meters of positive elevation gain and a total distance of 165 kilometres.
By tonight, we’ll already know the winner. Naturally, breakfast television is entirely devoted to this spectacle. Reporters say the leading runners have already reached the cirque of Mafate, the most inaccessible of the three. Live footage shows the favourites and the hallucinatory course they must overcome.
La Saline les Bains – Wave action at the reef
We’re taking it slower, enjoying our breakfast under the palm trees of La Saline les Bains. In the distance, about 400 meters from shore, high curtains of white spray reveal the presence of a coral reef just beneath the water’s surface. That’s where the waves of the Indian Ocean lose their strength. What remains are gentle ripples that break softly on the sandy beach just a few dozen meters away from us. On this side of the reef it is pleasant to swim; beyond it, if we’re lucky, we might spot a humpback whale passing by.
To describe how the Piton des Neiges emerged from the ocean is to tell only half the story of La Réunion
The sun confidently rules over this tropical scene. The bright blue sky promises a brilliant day. There’s no rain to fear here. Before noon, the thermometer will rise to 32 °C (90 °F), as we’ll soon discover.
To describe how the Piton des Neiges emerged from the ocean is to tell only half the story of La Réunion. Because the Piton des Neiges is a volcano that has been dormant for twelve thousand years. Three cirques are silent witnesses to its most recent collapse. We should not expect any more volcanic activity there
Aire de la Grande Corniche – Manapany
But that does not apply to the hotspot that gave rise to the Piton des Neiges and that still lies beneath La Réunion. Over time, it began to push lava upward again, and as a result, about 530,000 years ago, a second volcanic cone emerged above the water, some thirty kilometres from the Piton des Neiges. Because in the meantime La Réunion had shifted a little to the northwest
Very much alive is no exaggeration. In fact, because the Piton de la Fournaise is so young, it is one of the most active volcanoes in the world
Together, these two volcanoes now define the profile of La Réunion. In the northwest, you have the Piton des Neiges, a dormant volcano with three cirques. In the southeast, there is the Piton de la Fournaise, a volcano that is very much alive.
And very much alive is no exaggeration. In fact, because it is so young, it is one of the most active volcanoes in the world. Since 1640, there have been 183 recorded eruptions, including 37 in just this early 21st century alone.
Le Gol sugar factory
Fortunately, it is a shield volcano. Explosions are rare in such volcanoes. Lava usually just gushes out of the crater and flows down the slope. Still, very occasionally there is an explosion. One occurred 4,700 years ago. It must have had a force comparable to that of Mount St. Helens in 1980 in the United States. The result of that explosion was the collapse of the Piton de la Fournaise, leaving behind a caldera 400 meters deep and about eight kilometres in diameter. Later, the eastern wall of that caldera collapsed. The horseshoe-shaped plain that was created, with an opening toward the sea, is known as the Enclos Fouqué.
Megatsunamis already have produced wave heights of over 500 meters
That’s good news, because it means that during an eruption, lava has no other escape route than to flow neatly toward the sea. As such, it poses no threat to the population on the other side of the volcano. But it’s also bad news, because the entire eastern flank of the volcano is unstable and, in fact, at risk of collapsing. If that ever happens – and it will happen someday – it would trigger a megatsunami. Compared to that, an “ordinary” tsunami, like the one on Boxing Day 2004 in the Indian Ocean, is a minor event. While a regular tsunami can generate waves up to 30 meters high, megatsunamis have produced wave heights of over 500 meters.
Ruins of the Baril sugar factory
That volcanic region in the south eastern corner of La Réunion is on our itinerary for today and tomorrow. It is largely uninhabited; construction is even prohibited in most places due to the threat of volcanic activity. It is not for nothing that they dubbed that remote area the Sud Sauvage – the Wild South.
With Max as our driver and Marie-Annick as our tour guide, we set off. Today, we’ll explore the lava tubes of the Piton de la Fournaise; tomorrow, the caldera of that same volcano. Magnificent, unique, and unforgettable – that’s how Marie-Annick describes the experience that awaits us in the lava tubes. Our expectations are high.
It is not for nothing that they dubbed that remote area the Sud Sauvage – the Wild South
Route des Laves
Max steers his Mercedes Sprinter uphill through the coastal strip until we reach the Route des Tamarins, as the ring road is called here. It’s a very comfortable highway, with two asphalt lanes in each direction. Its fame is largely due to the many engineering works needed to bridge the numerous ravines – no fewer than 123 over a distance of just 33 kilometres.
Just before Saint-Louis, Le Gol appears through the window – one of La Réunion’s two sugar factories. One hundred thousand tons of sugar leave this factory each year. The plant generates its own electricity using bagasse, the fibrous residue of sugarcane stalks, which serves as fuel.
Gradually, the terrain becomes more hilly. The four-lane road narrows into a winding two-lane road that snakes its way over the foothills of the mountains. The Route de la Grande Corniche, they call the N2 here – a nod to the French Riviera. In the village centres, gendarmes endormis slow down the busy traffic – sleeping policemen is the local nickname for speed bumps. From the Aire de la Grande Corniche, we look out over the coastal village of Manapany and the Indian Ocean, where the calm sea water turns grey beneath a thick blanket of clouds.
Crumbly slopes of solidified lava emerge higher up from beneath the white cloud cover
Grand Brûlé – Lava field (2007)
Then we pass Saint-Joseph, the southernmost city of… Europe. Human habitation becomes sparser now. The Sud Sauvage is approaching. Yet villages still appear regularly, complete with schools, shops, and places to eat and sleep. Clearly, there’s no reason for concern here, even though the crater of the Piton de la Fournaise lies only fourteen kilometres to the north. But during eruptions, lava always flows eastward through the opening in the caldera. The common belief is that the volcano will continue to honour that pattern in the future.
The ruins of the Baril sugar factory remind us that sugar was also processed in this remote area. But when the factory started in 1863, the heyday of artisanal sugar cane cultivation was already over. The factory had a very short life – after barely five years, it shut its doors. From then on, starch was produced from cassava, until a cyclone in 1932 also put an end to that.
To name a cape “wicked,” you must have a good reason. At Cap Méchant, they certainly did. The narrow rocky point juts out into the sea like a long stone pier, about a hundred meters long. Pirates used to place false lights along the coast here, tricking ships into believing they had reached a harbour and luring them toward this dangerous spot. If the ships smashed against the dark rock, the pirates only had to collect the spoils.
The 2007 eruption was probably the worst since records began in 1640
Lava field (2007)
Now that we’ve left Saint-Philippe behind, things are getting serious. The Route des Laves leads straight through the Grand Brûlé, the area where lava flows to the sea during eruptions. Building is, of course, not allowed here – this is pure wilderness. People here don’t speak of the lava flow of the Piton de la Fournaise, but rather of the lava flow of 2004, the lava flow of 2007, the lava flow of 2019, and so on. If you look at Grand Brûlé on a satellite image, you’ll recognise multiple lava flows running into the sea – like an octopus sprawled on land, with its tentacles reaching toward the water.
The most recent lava flow dates from 2 July 2023, barely three and a half months ago. But it’s hardly considered worth mentioning, since the lava didn’t even reach the sea. April 2007 was a very different story. That was probably the most severe eruption since records began in 1640. The lava took just twelve hours to reach the sea. In total, 120 million cubic meters of lava were released – enough, in theory, to cover all of La Réunion in a five-centimetre thick layer. For a time, even the village of Le Tremblet was threatened. According to legend, the lava flow was on its way to engulf a small church, but split in two just before reaching it, leaving the church untouched. Pope John Paul II reportedly called it a miracle.
In some parts, the solidified lava was sixty meters thick. Restoring the road was a real feat – it took no less than seven months
Lava field (2007)
The Route des Laves also took a hit. In some parts, the solidified lava was sixty meters thick. Restoring the road was a real feat – it took no less than seven months. But there was also good news. The outflowing lava had made La Réunion a little bigger, reportedly by about thirty square kilometres. And scientists were able to identify many new fish species, which had floated up from the deep sea after the scorching lava significantly heated the seawater.
It's an impressive yet desolate sight: these crumbly slopes of solidified lava that emerge higher up from beneath the white cloud cover. Behind it lies the hidden Piton de la Fournaise, the source of all this destruction. Vegetation is scarce in this black desert. Only the erica reunionensis, an endemic heath species, pops up here and there. It’s a typical pioneer species, usually the first to colonise these lava fields.
Don’t expect a path, Simon warns us. It’ll be dark, sometimes slippery, with a low ceiling and a very uneven floor
On the way to the lava tubes
Simon and Julien, two experienced speleologists, await us at the 2004 lava flow – the only place where you can visit the lava tubes. We’re immediately handed helmets with adjustable headlamps, gloves, and knee pads. Don’t expect a path, Simon warns us. We’ll have to make our way over crumbly lava to reach the tunnel entrance. Caution is advised, even after we’ve descended into the tunnel. It’ll be dark, sometimes slippery, with a low ceiling and a very uneven floor. At one point, we’ll even need to crawl on hands and knees.
How such a lava tunnel forms isn’t actually that hard to understand, he continues. During a volcanic eruption, searing hot lava flows downhill. As it moves, it gradually cools – starting with the outer layer, of course. This forms a hard crust of solidified lava, while the inside remains liquid. In fact, this crust acts as an insulator, preventing the lava inside from cooling – as if it's inside a giant thermos. Once the volcano stops producing lava, the tunnel empties and becomes ready for our visit. So to speak.
Even on this rocky ground, a surprising number of green plants have managed to take root
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Cautiously, we follow Simon across the anthracite-grey lava rocks. The uneven terrain is challenging – it’s easy to twist an ankle here. Yet, even on this rocky ground, a surprising number of green plants have managed to take root.
In some places, the going is a bit easier. Simon calls this type of lava pāhoehoe – Hawaiian for smooth lava. It’s often referred to as ropy lava because the solidified lava resembles coiled rope. That’s because the lava was extremely hot when it solidified. This means it was less viscous – less sticky – and solidified while still in motion.
Pāhoehoe is Hawaiian for smooth ropy lava, ‘a‘ā is Hawaiian for stony rough lava
Pāhoehoe (ropy lava or smooth lava)
‘A‘ā (stony rough lava)
Elsewhere, it’s much harder to find a safe path. Sharp, irregular blocks of lava lie scattered all over. We best avoid these stretches, as it’s nearly impossible to keep your balance on such lava. Simon calls these blocks ‘a‘ā – that’s Hawaiian for stony rough lava. That name isn’t hard to remember, he grins, because ‘a‘ā is exactly what you’d shout if you walked barefoot over it.
This forms a hard crust of solidified lava, while the inside remains liquid
Entrance to the lava tubes
‘A‘ā forms from lava that is slightly cooler at the moment it solidifies. Because of its viscous nature, it barely moves as it hardens. That’s why it can take on the form of these rough rocks. Judging by appearances, white lichens seem to find a welcome foothold in that coarse texture.
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A few minutes later, we are down below, ducking beneath the low ceiling, marvelling at the strange world we've entered
They remind Simon of chocolate…
A fifteen-minute walk brings us to a gaping black hole. During the formation of a lava tunnel, it sometimes happens that cracks appear in the tube as it solidifies. Occasionally, this leads to a collapse. Simon calls that a stroke of luck, since it creates an entry point to the lava tunnel. A few minutes later, we are down below, ducking beneath the low ceiling, marvelling at the strange world we've entered. Here and there, long brown strands hang from the ceiling – roots from trees or plants at the surface.
This is how multi-layered lava tubes sometimes form. Simon even refers to it as a millefeuille of lava tubes
Lava tube with remains of a prototube (bottom right)
Simon immediately crouches next to a curious structure on the tunnel floor. Two parallel walls run down the centre of the tunnel. These are the remains of an older, smaller lava tube. Apparently, more and more lava had been fed in from above, eventually overwhelming this narrow tube. A second, larger tube formed over the original one and crushed it under its weight. This is how multi-layered lava tubes sometimes form. Simon even refers to it as a millefeuille of lava tubes.
Their nipple-like shapes indicate that they are lava formations that solidified while dripping from the ceiling
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Roots of plants |
You can still see on the tube wall how high the lava once flowed. Further on, smooth brown structures hang from the ceiling, gleaming in the light of our headlamps. They remind Simon of chocolate. Their nipple-like shapes indicate that they are lava formations that solidified while dripping from the ceiling – just like stalactites in a limestone cave, except that real stalactites keep growing as long as water continues to drip, whereas this lava solidified into its final shape once and for all.
At a wider part of the tunnel, Simon has us sit on a few rocks as if we were in a grandstand. A perfect place for a group photo, and also a fitting moment to experience complete darkness, as we switch off our headlamps.
A deep, tubular cavity in the tunnel wall is a reminder of a tree trunk that once carbonised there
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Transition between rock (top) and lava (bottom)
A deep, tubular cavity in the tunnel wall is a reminder of a tree trunk that once carbonised there. Water drips from the ceiling all around us, as it easily penetrates the thick lava layer. Then we reach a section about fifteen meters long where we have to crawl on hands and knees. Coincidentally, that part lies directly beneath the highway. That turns out to be a bonus, as it’s dry there thanks to the asphalt layer above, which doesn’t let water through.
Our fascinating exploration of this intriguing underground world lasted an hour and a half. All that time, we covered barely five to six hundred meters
With some effort, we climb back to the surface through a crack in the lava. Our fascinating exploration of this intriguing underground world lasted an hour and a half. All that time, we covered barely five to six hundred meters, Simon tells us. And the helmet proved to be an essential item – countless times, we bumped our heads against the low ceiling.
A toast to the successful expedition is in order, Simon says. And we wholeheartedly agree. In the parking lot, he even has a punch ready for us. By chance, our eye falls on the registration code on Julien’s license plate. It’s not 974, the code for La Réunion. That’s right, he confirms – the car was registered in Alsace, France. He had it shipped here by boat.
Climbing out of the lava tunnel |
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Just before six o’clock, we arrive at our hotel in La Saline les Bains. The climax of the Diagonale des Fous is drawing near. At 8:21 pm, it finally happens: the first ultrarunner crosses the finish line in Saint-Denis. It’s 30-year-old Aurélien Dunand-Pallaz from Haute-Savoie. He took 23 hours, 21 minutes, and 7 seconds to complete the 165 km course with 10,000 meters of elevation gain – an average of about 7 km per hour. To understand how impressive that is, consider that the second-place finisher took nearly forty minutes longer.
Also noteworthy is the performance of the first woman, American Katie Schide, who completed the race in twenty-seven and a half hours. While that’s four hours more than the winner, only twelve men finished ahead of her.
He took 23 hours, 21 minutes, and 7 seconds to complete the 165 km course with 10,000 meters of elevation gain – an average of about 7 km per hour
Aurélien Dunand-Pallaz during his passage through Marla (screenshot)
As for the other participants, they must cross the finish line by Sunday morning – two days from now – at nine o'clock at the latest. That’s the 60-hour time limit. Otherwise, they won’t even be listed in the official results.
Saturday 21 October | Grand Bassin – Route du Volcan – Piton de la Fournaise
Up at the crack of dawn, because today’s itinerary includes the absolute highlight of the trip – both literally and figuratively. Yesterday, we traversed the barren wilderness of the Grand Brûlé; today, we're setting out in search of the cause of all that destruction – the Piton de la Fournaise, the island’s only active volcano. To fully enjoy it, we need to arrive early. As the day progresses, clouds often obscure the volcano from view.
Today, we're setting out in search of the cause of all that destruction – the Piton de la Fournaise, the island’s only active volcano
The day begins promisingly, with radiant sunshine reigning unchallenged across the blue sky. Our driver Max takes us southward along the familiar ring road to Saint-Pierre, the island’s third-largest city with over 85,000 inhabitants. The city appears to have regained its calm after last night’s chaos surrounding the start of the Diagonale des Fous.
Grand Bassin
We now leave the ring road behind and head into the mountains, following the Route des Plaines – a fairly comfortable asphalt road and the only thoroughfare that cuts across the island, from Saint-Pierre on the southwest coast to Saint-Benoît on the northeast coast, a distance of about 58 km. The relatively straight route divides two vastly different volcanic landscapes: to the left, the three calderas surrounding the dormant Piton des Neiges, which hasn't stirred in 12,000 years; to the right, the barren lava fields of the hyperactive Piton de la Fournaise, which erupted just a few months ago.
An expression like mon ti’ caf (“my little Cafre”) is actually considered endearing
Once we’ve passed Le Tampon, the climb begins toward the Plaine des Cafres, a plateau formed over time by erosion between the two volcanoes. This Plain of the Cafres owes its name to escaped enslaved people – the Cafres – who once hid here. The name may strike us as offensive. But this turns out to be a misconception. Whereas the term Cafre is considered a serious insult elsewhere in Africa – especially in South Africa, where it's comparable to the n-word in the United States – it carries no such weight on La Réunion. Quite the opposite: the celebration marking the abolition of slavery is called Fèt Kaf, and expressions like mon ti’ caf (“my little Cafre”) are actually considered endearing.
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Grand Bassin |
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You won’t find any saint-named villages along this Route des Plaines. Instead, we pass through the municipality of Le Quatorzième (“the Fourteenth”), which, not coincidentally, is 14 km from the coast. The pharmacy is called Pharmacie La 14e. Three kilometres farther, we reach Le Dix-Septième (“the Seventeenth”), where a butcher proudly operates under the name Boucherie du Dix-Septième.
By now, it’s 8:45 am. Looking back over our shoulders, we can see a blanket of clouds already stretching to the coast. Let’s hope they don’t move in further, so we’ll still be able to witness the Piton de la Fournaise in all its glory.
From a dizzying height of about 1,400 meters, we look straight down at the white houses of the village of Grand Bassin
Grand Bassin
But first, we take a short detour to the Belvédère de Bois Court. We assume it’s just another viewpoint, like so many others. But that turns out to be a serious underestimation. What we see here is almost beyond belief. From a dizzying height of about 1,400 meters, we look straight down at the confluence of two rivers, each having carved a deep, narrow gorge into the volcanic mountains. Far below, roughly 750 meters beneath our feet, we can just make out the white houses of the village of Grand Bassin.
Once down you will get to know La Réunion from tan lontan, La Réunion as the island used to be
Bringing down supplies to Grand Bassin (bottom left) |
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Around thirty families live there on the banks of the Bras de Sainte-Suzanne. You can only reach them on foot. A trail of about 16 kilometres winds its way down the steep slope. The descent takes three to four hours. Once down you will get to know La Réunion from tan lontan – La Réunion as the island used to be. There’s no electricity there, and no internet either. Twice a week, a cable lift – strictly prohibited for passenger use – brings supplies down. As it happens, the lift carriage, packed with goods, has just started its descent. The air is a bit hazy, but the weather is otherwise perfect for enjoying this stunning panorama.
Cascade Grand Bassin
Bourg-Murat is where we take the turn onto the Route du Volcan. But this Creole village owes its fame primarily to the presence of the Cité du Volcan, a museum dedicated to volcanology in general and to the Piton de la Fournaise in particular. The driving forces behind this museum were the volcanologists Maurice and Katia Krafft from Nancy. For twenty years, they travelled the world and captured volcanic eruptions under the most daring circumstances – resulting in an archive of more than 300,000 photos and 300 hours of film. In 1991, however, they were caught in a pyroclastic flow on the flanks of Mount Unzen in Japan, along with around forty other volcanologists and journalists.
In 1991 Maurice and Katia Krafft were caught in a pyroclastic flow on the flanks of Mount Unzen in Japan
Ancient volcanic cones in the plain around Bourg-Murat
Today, the Observatoire Volcanologique du Piton de la Fournaise is also housed in this museum. Its specific task is to monitor the volcanic activity of the Piton de la Fournaise around the clock. As the crow flies, the observatory is about fifteen kilometres from the formidable crater mouth – close enough, but not too close.
Via the Route du Volcan, we now drive straight into the epicentre of volcanic activity. Yesterday, we were on the eastern side of the volcano – the side where lava flows often appear – while today we are on the diametrically opposite, safe western side. From here, you can get very close to the volcano; you can even walk along the crater rim – although this is strongly discouraged. We won’t go that far anyway, as we don’t have the time.
If you were to imagine the volcano as a giant fortress, this valley would be part of its enormous moat
Valley of the Rivière des Remparts with Roche Plate in the distance
At first, the narrow Route du Volcan leads us through a pastoral landscape of green meadows and cows – of the Blonde d’Aquitaine breed, Marie-Annick specifies. There are no lush forests, but that has nothing to do with the tree line. When slavery was abolished in 1848, the formerly enslaved people became free citizens and no longer had to hide from slave hunters. They began building modest homes and lighting hearth fires – in August, temperatures here can drop to 0°C (32 °F) – and for that, they needed wood. Trees were felled on a massive scale. On the initiative of a biologist from Nancy, efforts are now being made to make up for the loss by planting Japanese pine trees.
After a landslide in 1965, the inhabitants had to leave their homes in a rush
Roche Plate |
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The landscape gradually transitions into a heathland with mostly low shrubs. We’re at an altitude of about 2,050 meters when the Belvédère du Nez de Bœuf comes into view. It’s not cold – quite the opposite – the sun is still doing its very best. Once again, we’re stunned by the spectacular view. This time, it’s the valley of the Rivière des Remparts that we overlook. The viewpoint is perched above a bend in the river, perfectly aligned with its course. It couldn’t be better positioned, as our view stretches through the impressive valley almost all the way to the sea, where clouds still hover above the coast.
The Rivière des Remparts isn’t very long – barely 23 kilometres – but it has created a very special valley. If you were to imagine the volcano as a giant fortress, this valley would be part of its enormous moat. Its story begins with a collapse some 300,000 years ago. A long, vertical wall from north to south appeared in the landscape due to subsidence. This wall blocked all the rainwater that had previously flowed down the western flank of the volcano to the sea. From then on, all that water had to exit through the same channel. As you can imagine, this led to a great deal of erosion. The valley grew deeper and deeper.
Via the Route du Volcan, we now drive straight into the epicentre of volcanic activity
Route du Volcan
But the volcano didn’t stop there. It regularly produced lava that also flowed down the slope and refilled the valley floor. Then, around 65,000 years ago, another collapse occurred, this time higher up the slope. As a result, lava could no longer reach the valley. Water had triumphed over lava. A striking illustration of the interaction between these two natural forces can still be seen in the river’s upper course, where water mostly flows underground through old lava tubes.
On our right, an enormous lava plain has appeared – the Plaine des Sables – seemingly as flat as a billiard table
Plaine des Sables
In the distance, we can just make out the white houses of Roche Plate on the valley floor. Like Grand Bassin, this village is only accessible on foot. After a landslide in 1965, the inhabitants had to leave their homes in a rush. It took many years before they gradually returned. Nowadays, hiking tourism is the main reason people stay there.
The Route du Volcan continues to climb, winding like an unassuming brown ribbon across the barren slopes. The landscape becomes a bit monotonous now. There are no more trees, only knee-high shrubs. About every ten meters, a white stone is placed on either side of the road to help drivers orient themselves in case of sudden dense fog.
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Then, suddenly, right at the top of the Pas des Sables, as Max begins the first turn of the descent, we are completely taken aback by the scene unfolding below us. On our right, an enormous lava plain has appeared – the Plaine des Sables – seemingly as flat as a billiard table. It looks like a lunar landscape; nothing grows there. In the distance on the horizon, a few bare mountains rise, part of the caldera of the volcano. Beyond them, right in the middle, we can just make out the peak of the Piton de la Fournaise, standing 2,632 meters tall. We ourselves are 2,437 meters above sea level.
It looks like a lunar landscape; nothing grows there. In the distance on the horizon, a few bare mountains rise, part of the caldera of the volcano
Half a dozen hairpin turns later, we’re at the bottom. The Route du Volcan is now an unpaved dirt road that cuts straight through the Plaine des Sables. But that doesn’t matter. It’s another five kilometres or so until we reach the parking area at the Pas de Bellecombe, and then a few hundred more meters on foot to the viewpoint, right at the top of the caldera.
Higher up the slope, we spot anthracite-grey patches of ‘a‘ā, the crumbly lava blocks we encountered yesterday
Piton de la Fournaise
It’s fairly busy there, as this is the spot everyone wants to see. And rightly so – the sun-drenched landscape gradually revealing itself behind the caldera is breathtaking. From an altitude of 2,319 meters, we overlook the horseshoe-shaped plain, with the Dolomieu, the largest active crater of the Piton de la Fournaise, at its centre.
Scattered across the plain lie several other, smaller volcanic cones. The most striking – and also the most photogenic – is the ochre-coloured Formica Leo, an elliptical structure about a hundred meters long.
Formica Leo
Higher up the slope, we spot anthracite-grey patches of ‘a‘ā, the crumbly lava blocks we encountered yesterday. They are likely remnants of recent small eruptions.
You can get very close to the volcano; you can even walk along the crater rim – although this is strongly discouraged
‘A‘ā (stony rough lava)
Fortunately, the Piton de la Fournaise is a shield volcano – a gently sloping volcano that pushes out its lava relatively calmly, which then flows over the surrounding area. This behaviour is typical of volcanoes formed under water. Stratovolcanoes, like Kilimanjaro, Popocatépetl, Fuji, or Eyjafjallajökull, on the other hand, with their steep volcanic cones, are much more dangerous. Their eruptions are always accompanied by massive explosions – like a champagne bottle suddenly popping its cork. Volcanic material is then hurled high into the air, often resulting in deadly pyroclastic flows and volcanic ash fall. Such volcanoes are usually found along fault lines in the Earth’s crust.
If you wanted to design a relatively safe volcano that still offers some spectacle every now and then, you could use the Piton de la Fournaise as a model
All in all, this is a remarkable environment. If you wanted to design a relatively safe volcano that still offers some spectacle every now and then, you could use the Piton de la Fournaise as a model. You start with a shield volcano, where lava emerges relatively calmly from the crater, you build a high caldera around it to protect the surrounding area, and within that basin, you provide an outlet to the sea to drain away the hot lava.
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Still, we shouldn't forget how unpredictable a volcano can be. What whims the Piton de la Fournaise may have in store for the future, only time will tell.
A good distance outside the Enclos Fouqué, more than eight kilometres from the Dolomieu, we hike to the Commerson Crater. Today, this crater no longer poses any threat. But two thousand years ago, it was a force to be reckoned with – even rivalling the Dolomieu in power.
In fact, its eruptions were explosive. That was due to the large amounts of underground water. The extreme heat from the lava superheated the water, turning it into scalding steam. The crater became a kind of pressure cooker, until the lid blew off. Those explosions only ceased when an opening formed in the side wall, allowing the lava to escape. We already know that story – the lava flowed into the Rivière des Remparts and undid the erosion previously caused by the water.
In January 1980, during the passage of a cyclone, no less than 6,430 mm of rain fell here in just 15 days
Commerson Crater |
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Water still plays a major role around this crater. The bone-dry surroundings may seem to contradict that, yet the microclimate here attracts an extreme amount of rainfall. In January 1980, during the passage of a cyclone, no less than 6,430 mm of rain fell here in just 15 days. That’s more than six times the annual rainfall Belgium typically gets.
Mist hangs over the road during the descent, little or nothing of the barren mountain landscape can be seen
Our driver Max and our guide Marie-Annick were absolutely right: to fully enjoy this landscape, you have to rise early. We see that clearly during the descent. Fog now blankets the road, the barren mountain scenery has all but disappeared, and from the Nez de Bœuf viewpoint you see nothing but white clouds. Luckily, the white stones by the roadside help guide us down.
Stella Matutina – Processing of sugar cane
After lunch, there’s even a short burst of rain – but we don’t mind, because we dive into the fascinating world of Stella Matutina, a former sugar factory in Saint-Leu that has been converted into a museum. The focus here is on the history of sugarcane cultivation. Not only are the technological developments and production processes covered, but especially the lives of the workers, enslaved people, and indentured labourers. It’s a huge hall, with the collection spread across three floors – including massive machines on the ground level that recall the dawn of industrial sugarcane processing. Naturally, we wrap up the visit with a little rum tasting.
Often you can hardly suppress a smile when you recognise the meaning of the Creole words
Stella Matutina |
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Creole price list |
It’s also fun to learn a few Creole words. Apparently, the relationship between this language and French is much like that between Afrikaans and Dutch. We notice this on an information panel in the museum. Often you can hardly suppress a smile when you recognise the meaning of the Creole words.
Lhër lé rouvèr (les heures d'ouverture) are from 9 hër édmi lo matin jiska 5 hër édmi laprémidi (9 heures et demie le matin jusqu’à 5 heures et demie l’après-midi) – meaning the opening hours are from 9:30 am to 5:30 pm. But ticket sales stop at 5 hër moins-l’kar laprémidi (5 heures moins le quart l’après-midi) – meaning 4:45 pm. Reduced rates apply for children depi 4 an jiska 12 z’an (depuis 4 ans jusqu’à 12 ans), for zétüdian (étudiants) and for zandikapé (handicapés) – meaning children from 4 to 12 years old, students, and people with disabilities.
In the evening, in La Saline les Bains, we enjoy dinner as the sun slowly sinks into the horizon in a reddish glow and watch two humpback whales frolicking just beyond the coral reef.
Jaak Palmans
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The place you never return from