On the Shetland Isles, on the far edge of Europe, a series of monumental stone towers – known as Brochs - once dominated the landscape. Aubrey sets off to discover what sort of community built the Broch towers and for what purpose.

On the island of Mousa, he visits the most complete Broch anywhere in Scotland and discovers its sophisticated architecture. Brochs are in commanding positions on the coast and many are within sight of another, raising the possibility that they were used for defence and communication. But who was the enemy? One idea is Roman slave traders. The real mystery is how these bleak islands could support a population prosperous enough to build the network of more than a hundred Brochs.

Aubrey visits a recently discovered site at Scatness, where a Broch is at the heart of an Iron Age settlement. Here there are finds of animal bone, barley grains, and metalwork which archaeologists from Bradford University are hoping will help to unravel the mystery of the Broch people.

Piecing together evidence from Scatness, from local fishermen, and crofters still growing ancient strains of barley, Aubrey works out how the ancient Shetlanders could have lived and even prospered. He finds evidence of a people who made good use of local resources such as soapstone, iron and copper. Using peat for fuel they seem to have been proficient metal workers. And bronze objects made from copper and tin suggest they were even trading, perhaps with Cornwall, to obtain the tin they needed.

Meanwhile, carbon dating of material from the Scatness Broch revealed a date of 400 BC, much earlier than expected. It rules out the theory that the Brochs were built as defence against the Romans.

It seems the Brochs may instead have been prestigious homes for the elite of society. Aubrey concludes that in the Iron Age, Shetland was home to one of the most sophisticated and successful communities in Western Europe.

Content last updated: 25/09/2003