First, wooden moulds were filled with hard-packed sand to create a basic structure.

Wooden moulds (largest 3m x 3m, smallest 60cm x 60cm) are filled with layers of sand and water.

This wet 'concrete' would have been carried to the site and packed into wooden moulds where it would set hard in a few days.

Decades later, turned wooden moulds, which were either covered in simple wrappings or much more elaborate coverings called satinings, were used.

They can either be decorated by hand or be made in special wooden moulds.