Cursus are intriguing monuments. Far bigger – and in many cases far better laid out – than anything that had gone before or was to follow in the next 3000 years. Leviathans that swallowed people and land; signalling devices probably to be read from above by the gods rather than on the ground by figures dwarfed by their dimensions. Stubbornly empty, these ‘British Nasca lines’ are nevertheless susceptible to reasoned enquiry that lays bare both their conceptual origins and their role in a society on a trajectory to individual power.