Incredible But True Incredible But True Human World History Makers Cities Of The World Art And Music Sporting Headlines Plant Life Fish, Amphibians, Reptiles Birds and Mammals Creepy Crawlies Marine Life Restless Earth Earth's Secrets Changing Weather Seas And Oceans Comparisons Amazing Structures Machines And Man World Of Inventions Travelling Around Mysterious Universe	Central Core The edge of the liquid central core of the earth is 5150km from the surface - more than a journey from Boston, USA, to the North Pole. The Earth's core   Previous: Back Book: Incredible But True Section: Incredible But True Chapter: Restless Earth