Archaeological site Minières néolithiques de Petit-Spiennes in Mons

You're standing at the Neolithic flint mines of Spiennes, just southeast of Mons. At first glance it's mostly rolling countryside. But take a close look at the ground. Sharp little chips of flint are everywhere. There are millions of them, and they're no accident. They're the waste left by stone workers who were busy here thousands of years ago. For more than two thousand years, from around 4300 BC, people dug flint out of this hill. Flint is perfect for axes and razor-sharp blades. Across more than a hundred hectares they sank thousands of pits. A shaft was about a metre wide and could go down as deep as sixteen metres. At the bottom they dug side galleries, some up to seven metres long, using flint picks and tools made of deer antler. Only the best stones went up to the surface. The rubble was simply packed back into old galleries. Up top, the nodules were knapped straight away into rough axe shapes. These were traded as far as about a hundred and fifty kilometres away, and often only polished at their destination. With axes like these, early farmers cleared forests and built huts and canoes. For a long time nobody knew what lay here. Around the 1840s, workers at a nearby quarry noticed strange old pits. Then in 1867, railway construction laid bare twenty-five shafts, and scientists took notice. Digs turned up pottery, bones of cattle, pigs, goats and sheep, and even human skeletons. Since 2000 the site has been a UNESCO World Heritage Site, as one of the largest and oldest flint mines in Europe. So what's inside? The SILEX'S visitor centre, in the area called Petit-Spiennes, has an exhibition and a multimedia show about the mines and the people who lived and worked around them. Best of all, you can usually climb down into an actual mine shaft. Just note that the mines are only open on certain days or by appointment, so check the SILEX'S website before you go.