Book excerpt: Older that the Egyptian pyramids, older than Stonehenge, the tomb at Newgrange in County Meath, Ireland, is one of the oldest structures in the world. For 5,000 years it has housed the remains of a formidable Stone Age people, sheltering the spirits of the long dead from the outside world. Modern archaeological techniques have revealed much about the lives of our Stone Age ancestors, but questions about the tomb at Newgrange remain. Why did a group of Megalithic settlers spend years building a massive tomb? How did they move the huge boulders? What do the symbols inscribed on the stones mean? The author attempts to piece together the clues left behind by this extraordinary Stone Age civilization.