What you need to know about England's 'hidden medieval city'

What's happened?

Archaeologists say they have discovered the largest 'unknown' medieval royal palace ever found in England.

Using ground-penetrating 'X-ray' technology, a team from the University of Southampton have found a 12th century palace buried under what was originally an Iron Age fort at Old Sarum, the original location of Salisbury, in Wiltshire.

As well as the 170m long, 65m wide palace complex, which has walls 3m thick and is arranged around a large courtyard, dozens of ordinary houses were found, effectively allowing archaeologists to produce a detailed plan of what was once a major political and religious centre in Norman Britain.

• Artist's impression of barons swearing allegiance to William the Conqueror in 1086

Why are archaeologists so excited?

Professor David Bates of the University of East Anglia, a leading authority on Norman England and author of the key modern study of the Norman world, The Normans and Empire, said the mapping of Old Sarum was a "discovery of immense importance".

"It reveals the monumental scale of building work taking place in the earlier 12th century," he said.

Kristian Strutt of the University of Southampton, the archaeologist leading the geophysical survey, added: "Archaeologists and historians have known for centuries that there was a medieval city at Old Sarum, but until now there has been no proper plan of the site. Our survey shows where individual buildings are located – and from this we can piece together a detailed picture of the urban plan within the city walls."

• An 'X-ray' of the structures buried underneath the ground

What happened to Old Sarum?

Around 140 years after it was built Old Sarum was abandoned and relocated, in some cases brick by brick, to Salisbury two and a half miles to the south, because the political and diocesan centre of the city was apparently too cramped and exposed to the elements.

• An aerial view of the site

What happens now?

Geophysical survey work will continue to rediscover more secrets that Old Sarum has to give up.

Because the city was abandoned not long after it was built, in relative terms, and it is located on what is now a green field site, it offers academics a unique opportunity to study a Norman city.

(Pictures: English Heritage / University of Southampton)

Read more about the discovery at Old Sarum

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