Marine life certainly received a kick-start, but how was our patch of land faring in the meantime? We were located on the northern edge of Gondwana, but 480 million years ago parted company from it. Magma flows broke through the earth's crust in the area to the south of our country. ‘A big continent like Gondwana was doomed to break up,’ said Piessens, ‘because it was holding in the heat of the magma that lay below. And that's something that it couldn't have continued doing forever. The magma will find a weak spot and worm its way out through the surface.’ So wherever the ground is ripped open, lava gushed out and volcanoes were formed as well, causing new soil made of basalt to accumulate from the lava, once it had cooled. The magma flows then kept on coming, driving a wedge between Gondwana and our country, pushing us further and further apart.

‘Over time, a rift valley came to exist, as in the East African rift. That valley then filled with ocean, similar to the Red Sea today. The area that is now Belgium was drifting away from Gondwana at a rate of ten centimetres per year – which, in geological terms, is at rocket speed. The micro-continent thus created is called Avalonia. Avalonia was shaped like a gaiter, and we were on its southern edge, in the heel.

Can you actually find out all of this information from one of the whetstones found in Vielsalm? ‘The Belgian grindstones are one of the witnesses to our country's gradual separation from Gondwana. The stones themselves are full of manganese and iron from deep inside the earth. Those metals were spewed into the air by volcanoes. Southern Belgium was below sea level at the time, in calm waters. Dust and ash swirled down and the manganese and iron they contained, along with clay and silt particles, settled in the basin. These are the greyish-purple layers. The region around Brussels was largely above water, and lime (calcium carbonate) accumulated in the shallows. Part of that consisted of the tiny skeletons of extinct sea creatures.

When subterranean turmoil occurs, a calcareous package of that type slides towards the deeper and calmer waters of the south, like a cloud of dust underwater. Once there, the pale lime is deposited on top of the metallic clay layer. Every yellow streak here, and there are an awful lot of them, bears witness to a period of powerful volcanic eruptions at the time when our country became separated from Gondwana. It must have been a very eventful period. With every eruption that took place, Avalonia become more consolidated than before.’ 

Not only the patch of land we now call Belgium, but also the southern half of Ireland, Wales, England, northern France, the Netherlands, Germany, a piece of Denmark and part of Poland were located on the continent of Avalonia. In other words, the area that would later come to form the heart of North-West Europe. And though it may come as something of a surprise that they were located together, Avalonia also included part of the east coast of the US and Canada. Avalonia is named after Avalon, a peninsula off the Canadian coast, where the same 540-million-year-old rocks have been found as in North-West Europe.

So you could walk, as it were, from Belgium to the east coast of Canada and the US, from Brussels to Boston. Occasionally, you would have had to take a ferry, because some stretches lay below sea level. 

Three hundred million years later, when long-necked dinosaurs roamed the earth during the Jurassic period, Europe and North America would drift apart and the Atlantic Ocean would come between them. That "rifting "is still taking place at the speed of a growing fingernail: two to five centimetres a year. And yet at times it creates turmoil – just ask the Icelanders, the residents of the Azores or of other volcanic islands on the Mid-Atlantic Ridge.

Geologically speaking, Belgium experienced so much drama because for 180 million years it was on the edge of continents and was therefore vulnerable to collisions: on Gondwana (northern edge), on Avalonia (southern edge), and also after the merger with Baltica and Laurentia (southern edge). The latter would trouble us around three hundred million years ago - by which time we were in the Carboniferous period. The great continent of Gondwana, from which we had parted, was catching up and was on its way to clash with us. That would go on to become the Variscian or Hercynian orogeny, the second great event leading to the formation of mountains. It brought the whole world together to form the supercontinent Pangea.

The collision created part of the Appalachian Mountains in the west, resulted in the formation of the Ural Mountains in the east and caused Western and Central Europe to be pushed upwards. Our Brabant and Ardennes mountains, which had been flattened in the Devonian and Carboniferous periods due to erosion and then covered with clay, sand and lime sediments, were again pushed upwards to form a medium-sized mountain range, and our area became folded up once again like a tablecloth into A's (antiforms) and U's (synforms), with fracture surfaces and shifts as well. 

‘That actually makes Belgium extremely interesting from a geological point of view,’ Kris concludes. ‘We are such a small area, but were deformed so often that ancient layers were pushed to the surface. More than that, our country includes geological phenomena that represent all of the sequences that took place in the last five hundred million years, from the Cambrian period to the Ice Age. You can actually visit each one, take samples of them and look for fossils. The geology in Belgium is a very good library: from it, you can read just about the entire story of the planet and of life itself.’