 When you enter a cave on your own, you will see that it has a very strong impact on you physically. It's like entering a church. It has an impact on your mind and on your imagination. And the same way a cave is perhaps even more extraordinary because there's something, to my mind, wonderfully organic about caves. And also something timeless because you don't know if it's night or day. And it's magical. There is something magical about the underworld.