Question: What's the furthest any human being has travelled towards the centre of the earth?

Pete Etchells answered on 21 Jun 2012:

Great question! I think it’s been done on land through the deepest mine in the world – the TauTona gold mine in south africa goes down 3.9 km. James Cameron (the director of Titanic) recently led an expedition in a submarine to the bottom of one of the deep sea trenches, and went down about 11km. The deepest man-made hole is about 12 km, but I don’t think anyone’s actually been down it. These depths, though, aren’t actually deep at all – the radius of the earth is about 6,000 km!