Český Krumlov might be all about tourists these days, but it wasn’t so long ago that mining was king in these parts. This is the Czech Republic’s last graphite mine, open since 1975 but abandoned until recently, now lifting the lid (or the hard hat, in this case) on the proud mining history of South Bohemia. The underground mine stretches almost 2km, although the less mobile will be thrilled to hear that this is traversed by train. Good for kids, too.