Some time 6,000 years ago, the members of a now long-forgotten tribe dragged and lifted carefully chosen stones into place and built Ireland's first Temple of Stone. Over the next 2,000 years, hundreds more megalithic tombs were built across the country and then, around 2000 BC, the building stopped and the knowledge of what these remarkable stone structures meant to their builders was lost. After 4,000 years of silence, however, the stones are no longer mute. Every year, archaeologists discover more about these enigmatic monuments and instead of a single, simple answer to the question of what the megalithic tombs meant to those who built them, there is a multitude of answers, each one more intriguing that the next. As the Office of Public Works celebrates 40 years of the winter solstice at Newgrange and we enter Samhain, the Celtic New Year, Carleton Jones brings together the interpretations surrounding our megalithic tombs in a fully-illustrated popular format, shedding light on our ancestors belief systems and rituals and their deliberate manipulations of the world around them, often with drug-induced hallucinations. All key sites in Ireland are discussed with 100 Sites Worth Visiting listed in a final chapter with photos, maps and detailed directions.