Using his own long experience as a professional archaeological surveyor and after five years' patient computer-reanalysis of the earthwork and stone circle, Anthony Johnson reveals in this brilliantly argued detective story how he solved the key mystery of Stonehenge. Locked within the symmetry of the stones are precise formulae which determine their numbers, spacing and relationships. As a result of this revelation, the whole rationale behind Stonehenge and other major prehistoric sites can be reassessed.