Things have changed so much, so quickly, in the last couple of hundred years. We now live our lives indoors - from the house to the car to the supermarket to the office. This indoor life, fuelled on coco pops, pot noodles and ready meals, gaudily decorated with commercials, soap operas and MTV, seems so ordinary, but is in fact obscure and totally removed from the bulk of human experience over the last fifty thousand years.

For me, these works of stone and earth say something about what it really is to be human. To visit these old places is to share a set of experiences which humans have enjoyed and endured throughout the length of their existence as a species. The fresh blast of the wind and rain, the roughness of stone, the brightness of a full moon or the perfect dark of a tomb. It's not just about imagining how things were millenia ago, it's also about realising that many things have never changed.