The first Bronze Age engineers broke ground around 5,050 years ago, with excavating tools made from deer antlers and cattle bones. The original development featured circles of wooden posts surrounded by an arrangement of banks and ditches.

Around 500 years later, the first stones were erected – still two millennia before the Romans invaded. These bluestones, weighing up to five tonnes each, were brought 400km from the Prescelli Mountains in South Wales.

The stones were probably transported on enormous rafts along the coast of Wales and up the River Avon. They were then dragged overland to Stonehenge, only to be abandoned for a century or so before the really serious work began…

The 30 giant upright stones that formed the outer circle – 17 of which survive today - weighed as much as 50 tons each. They are evenly spaced, 1.4m apart, towering 4m (13ft) above the ground. At around 2m wide and 1m thick, they taper towards the top and originally supported 3m lintels which formed a continuous circle.

The lintels were fitted end-to-end using tongue-and-groove joints. They were held in place with mortice and tenon joints, fashioned with stone hammers. Researchers estimate that teams of up to 600 men would have dragged these stones over rough terrain from the Marlborough Downs, 32km (20 miles) away.