The remains of a Norman castle similar to the Tower of London have been found buried under the court of a disused prison.

basketball court of Gloucester Prison. Archaeologists say the keep, which had
walls up to 12 feet wide and measured around 100 feet in length, would
have resembled the Tower of London [Credit: Andrew Higgins/SWINS]
The old walls of the keep, dating back to 1110, were unearthed by archaeologists investigating the site in the centre of Gloucester before it is redeveloped.
The castle was the first in Gloucester to be built of stone and housed three chapels, two drawbridges and a royal chamber for both the King and Queen.
Neil Holbrook, chief executive of Cotswold Archaeology, said: "I am surprised by what we found.
"I knew there was a castle but I had expected more of it to have been destroyed."
He said the design was thought to have resembled Canterbury cathedral and the Tower of London.

It housed three chapels, two drawbridges and a royal chamber for both the King and Queen.
Archaeologist said they were 'surprised' so much of the walls had survived beneath
the prison's basketball court [Credit: Andrew Higgins/SWINS]
He added: "It would have been a powerful symbol of Norman architecture.
"As you came to Gloucester you would have seen the cathedral and the castle, which is representative of how important the city was in Norman Britain."
The keep wall, which is 12 foot wide, was found just 60cm below the basketball court that would have been used by prisoners.
The keep itself is estimated to have been 30m long and 20m across, indicating how big the actual castle was.
It was used as the city jail for two hundred years prior before the prison was built in 1780 and the castle was demolished.

demolished in the 18th century. They said the remains give an idea of how
important Gloucester was in Norman England
[Credit: Andrew Higgins/SWINS]
The remains of the walls had been buried for more than 200 years.
Gloucester Prison closed in March 2013 and was bought by City and Country Group, which is running a public consultation on its future use.
It is not yet decided what elements of the castle will be taken into account when constructing the new build.
City and Country are considering what to do with the site and as a result of the dig finds they have altered plans to include elements of the sites history.
Source: Western Daily Press [December 09, 2015]