Looking at the subject of Dolmens, the huge ruins of ancient chamber tombs which are among the most striking and widespread relics of ancient Europe, this book stresses their importance for archaeologists, because of what they tell us about prehistoric burial rites and the insights they give into the structure of ancient society and the pattern of prehistoric religion. Until the 1970s, when radiocarbon dating overturned the old order in European prehistory, it was assumed that the megaliths of northwest Europe could be traced back to the western Mediterranean and from there to the ancient East. But we now know that the European monuments are older than their supposed precursors and that the chamber-tombs of Brittany vie with those of Portugal to be the oldest known structures in the world, well over 6,000 years old. This book, which covers chamber-tombs throughout the world, reveals the unity of purpose and construction which distinguishes them, but it also shows that megalith-building developed simultaneously in different parts of the world.