A classic exposition of the difficulties of dating a major monument and why it matters. Silbury Hill, one of the world's largest prehistoric earth mounds, is too valuable to take apart, so we are reliant on samples taken from tunnels and chance exposures. Presenting a new edition of thirty radiocarbon dates, the authors offer models of short- or long-term construction, and their implications for the ritual landscape of Silbury and Stonehenge. The sequence in which monuments, and bits of monuments, were built gives us the kind and history of societies doing the building. So nothing matters more than the dates…