It is one of the great historic centrepieces of the city, and over the next few years an ambitious project is aiming to transform Norwich Castle keep and give visitors the chance to step back in time to the world of the Norman kings.
Called Norwich Castle: Gateway to Medieval England, the £13m four-year project will transform the keep to its former glory as it appeared in the days of King Henry I.
Thanks to substantial funding from the Heritage Lottery Fund, much of the money is already in place to make the dream become a reality.
Tonight there will be a special launch at the castle for invited guests to mark the development stage of the project.
Once the whole project is complete, visitors will be able to walk on the reinstated principal Norman floor and explore the re-created royal palace, including its great hall. There will also be a British Museum Gallery of the medieval period and improved access for people with disabilities, including to the battlements where state-of-the-art technology will give people the chance to compare views of modern and medieval Norwich.
'This is going to be the leading heritage project in the country for the next few years,' said Dr John Davies, chief curator of Norfolk Museums Service, who is leading the project's core team that also includes Angela Riley (project officer), Dr Tim Pestell (senior curator of archaeology) and Paris Agar (assistant curator).
'Norwich Castle is an absolute hidden gem as it stands at the moment. This is going to make a magnificent contribution to and for the people of Norwich and Norfolk, and provide us with the national status that the superb building we have deserves.
'It's going to be a presentation that people can really understand and enjoy and engage with. It will be a focal point for the local community to enjoy and to use, and a major contribution to the sustainability of our service and a boost to the local economy.'
While there are big plans in place, much of the work in the near future will be happening behind the scenes away from public view.
Dr Davies said: 'It is logistically getting everything in place this next year; it's geared towards preparations, towards the visible element, the construction.'
The team is looking at appointing a quantity surveyor and a project manager who will start shortly after Christmas, and it is hoped the architect will be in place by Easter.
A key event next month will be a metric survey of the keep, to help with reimagining what the keep looked like as a palace and also at other times in its history. The work will mean the keep will be closed to the public for the first week of November.
Dr Pestell said: 'The metric survey is undertaking a very close structural survey of the building. It's something that we have got former attempts at but this is going to be the first time that it's been done so that we can see, stone by stone, elevations of all the internal walls of the castle. It will be a plan that is, if you like, an architectural plan but to an archaeological specification…we are going to be able to capture the whole history of the castle.'
Work is also going on to decide which objects from the British Museum's medieval collection will be brought to Norwich to be displayed alongside the castle's own artefacts.
Dr Pestell said: 'A fellow curator and I went to the British Museum a few weeks ago and began to look at the sorts of objects that we can have in our own museum…We have a very good collection ourselves but there's a difference between the sorts of objects the British Museum has and our own.
'Ours are largely drawn from archaeological context, so we can tell, if you like, the story of the common person in Norfolk.
'But what we've lacked as a museum is the very wealthy high-end objects that the British Museum was collecting in the early 19th century. For instance there's a lot of very high status pieces of Limoges enamel, carved ivories, sculpture, metalwork.'
A huge array of specialists and organisations are also being consulted and advising on many different parts of the whole project. It is hoped the architect's work will be completed by the end of autumn next year and all the key plans will be in place by the end of 2017, ready for construction to begin in 2018.
Running parallel to this the team wants to develop a medieval programme of events and activities for visitors, building on things such as this summer's Medieval Madness programme and the Norwich Medieval Mystery Plays staged in August.
There are plans for an exhibition in spring 2018 on the history of Norwich Castle.
But for now, there is lots more preparation work to make the whole vision a reality, and Dr Davies and his team are relishing every moment.
'It's a chance in a lifetime for us to work on this,' he said.
'We appreciate this, it is a terrific opportunity to do something which is going to last for posterity. It will be a landmark. It will go down in history, and similarly for the city. It's a wonderful, wonderful thing for us to be achieving.'
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