The Norwich architect entrusted to deliver the restoration of the city's Norman Castle Keep has described the job as a 'once-in-a-career' opportunity.
The multi-million pound project aims to restore the building's original layout of nearly 1,000 years ago, and transform the castle into the premier heritage and tourism destination in East Anglia.
It will be led by Norwich-based heritage architects Feilden+Mawson, under the guidance of partner Hugh Feilden, whose previous work includes London's royal palaces, the Palace of Westminster and the Treasury in Whitehall.
'It's a once-in-a-career opportunity,' said Mr Feilden, whose uncle and F+M practice founder, the late Sir Bernard Feilden, was a principal adviser and architect to Norwich Cathedral.
'It is a quite remarkable honour to have worked on major projects on both the castle and cathedral, which were built at the same time and are thought likely to have been designed by the same master mason,' he said.
The project will reinstate the correct floor level and room layout within the former royal palace, while the Norman Great Hall will be recreated and its history brought back to life.
Norfolk Museums Service has been awarded initial support by the Heritage Lottery Fund for a £9.2m National Lottery grant, along with funding of £462,400 to bring forward plans ahead of a full grant application being made.
Mr Feilden and his team will examine the work of Victorian architect Edward Boardman, who prepared plans for the castle's conversion from a prison into a museum in the 1890s, but was unable to complete them.
'Reinstating the internal floors was part of his vision, but the project ran out of money – or courage – to complete as he had envisaged. In a sense we will be completing his vision. But to do that it is necessary to take out some of the work he did,' said Mr Feilden.
Dr John Davies, project director and chief curator, said: 'Norfolk Museum Service is delighted to be working with Feilden+Mawson and [civil engineers] Conisbee. We are taking forward these most significant elements of our nationally important project which will transform Norwich Castle and benefit our future visitors, the people of Norwich, Norfolk and beyond.
'This project has not only a regional but also a national and international significance.'
Though work will begin immediately, it will be mainly paperwork and technical design – consensus decisions will be taken by the project team – with work on the castle fabric starting in 2019 and expected to take a year to complete.
'There is not a single right or wrong way of doing the things that have to be done – this is an absolutely unique project in Norfolk,' said Mr Feilden.
'The challenge is knowing what to keep – apart from everything. In archaeological terms, even the dirt on the walls is a valuable asset, but as a conservation architect I want to keep the building in use.
'That is how you generate income – the building is a tool that should be used, otherwise it becomes a monument and then you treat it in a different way.'
Despite his illustrious portfolio, Mr Feilden admitted that the prospect of working on such a major landmark in his practice's home city had a special allure.
'What we do is part considered logic, part inspiration and part insight from your subconscious. Because you are seeing the castle much more frequently, it means you are always thinking about it.'
Norwich Castle: Gateway to Medieval England
The four-year scheme, led by Dr John Davies, who is also the chief curator and keeper of archaeology at Norfolk Museums Service, will transform the inside of the historic castle keep, restoring its appearance to the time it was built under the great Norman kings.
Tomorrow's visitors will be able to explore the newly-recreated exquisite Great Hall and catch a glimpse what life was like in the time of Henry I in the early 12th century, complete with its banqueting table and minstrels' gallery, king's chamber and chapel.
Reconstructed Norman era spaces will be dressed with the magnificence of a royal palace and enhanced by digital displays.
The British Museum, which is collaborating over the project, plans to have a gallery in the castle, while the project will also provide a new arts venue for Norwich and Norfolk.
In medieval times Norwich Castle was one of the most important secular buildings across the whole of Europe. Over the centuries it has served as royal palace, prison and now museum.
Dr Davies, whose dream is to restore its appearance to that of the historic and architectural integrity of Norwich Castle, describes it as 'one of the largest and most elaborate of the great Romanesque castles in the whole of Europe'.
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