It has been a courthouse, a prison, an armoury and a council chamber during its six centuries of existence.Now another part of one of Norwich's most historic buildings is being brought back into use as it celebrates its 600th anniversary.

It has been a courthouse, a prison, an armoury and a council chamber during its six centuries of existence.

Now another part of one of Norwich's most historic buildings is being brought back into use as it celebrates its 600th anniversary.

The Oak Room in the city's Guildhall is to be reopened by Norwich Heart (Heritage Economic and Regeneration Trust) after being out-of-bounds for 15 years.

The oak-panelled room, under the eaves of the ancient building, was formerly home to the Norwich Area Tourism Agency but was closed off under fire regulations. Now plans are being drawn up for access and fire prevention work.

Once reopened, the room could be used by Heart as a volunteer bureau.

Norwich City Council has already invested nearly £500,000 in the Guildhall over the last seven years and is currently looking at other ways to improve access to the building.

The council said the latest move, which comes a fortnight after it announced plans for a £4m refurbish-ment of the nearby Memorial Gardens, underlined its commitment to preserving the city's heritage.

The authority has spent £490,000 on the Guildhall since 2000, including £150,000 on stabilising the structure of the building which involved many pieces of flint on the buttresses being removed, numbered and put back.

All windows including stained glass were reglazed using the original glass at a cost of £92,000 and other work has included the installation of new boilers and a security system. Every year about £11,000 is spent on a general maintenance and repairs.

When Norwich Heart set up offices in the Guildhall in early 2006, most of the building was still out of use. Since then it has refurbished and the organisation occupies three rooms, providing jobs for eight full- and part-time staff.

The Norwich Blue Badge Guides have also set up a library there.

Heart chief executive Mike Loveday said: “When we moved in the building was still three-quarters empty. Since then we've not only provided a viable use for significant elements of the building by using it as our headquarters but facilitated use of and access to most of the rest of the building on a temporary basis.

“Our proposals to convert the Oak Room to a volunteer bureau will extend the beneficial use of the building further. The Guildhall is a building of national importance but Norwich has a lot of other buildings of equal or greater value - St Andrew's Hall and the churches, for instance - and so we need to attract and prioritise resources to do the job in a strategic way, rather than responding to isolated calls for action.

“The city council, Eeda (East of England Development Agency) and Heart have all committed significant sums to repairing, reusing and opening up the building and, while we've still got some way to go, we are making progress.”

Chris Dady, Norwich City Council's head of asset and city management, said: “The council is seriously looking at how we can further improve the access to the upper floors of the building. This includes the old chamber and courtroom and how to make the best use of the whole building.”

The Guildhall is also home to Angels Crystal Shop, Caley's Cocoa Café, Creative Arts East and the Sheriff's parlour.

Sheriff of Norwich Nick Williams said: “As Sheriff, it is a pleasure to have the use of the parlour in The Guildhall for a year, especially this year as we celebrate the 600th anniversary of its construction.

“It clearly requires sensitive refurbishment and I look forward to this being carried out.”

GUILDHALL HISTORY

The Guildhall was mostly built between 1407 and 1413 after Norwich was given more powers to self-govern in a charter of 1404. It was the largest and most elaborate city hall outside London, reflecting Norwich's status as one of England's wealthiest provincial cities.

From about 1413 to 1985 it served a vital civil function as a venue for council meetings and court hearings, covering everything from the most minor to the most serious of offences. Only with the building of a new City Hall in 1938 and the opening of new court buildings in 1985 have most of these functions ceased.

The Guildhall's 14th century undercroft, which was part of the old tollhouse that had previously occupied the site, was used as a dungeon into the 17th century. Its most famous inmate was Protestant martyr Thomas Bilney.

A Georgian courtroom now houses the Caley's Cocoa Café. This room was the original “free prison” where unshackled prisoners were kept until 1597.

It then became the new Cloth Hall before being converted to house the County Assizes, following a fire in the Shirehall in 1747. It later became the Court of Record, and then a Tourist Information Centre until this was relocated to the new Forum building in 2002.

Beneath it is a basement containing police cells which were in use until the early 1990s.

The former Great Chamber, on the first floor, was designed for meetings of the full medieval council, as well the assembly of 60 elected by freemen in the city's four wards.

It was also used by the old Sheriff's Courts dealing with minor offences. It now contains a virtually intact late Victorian courtroom, used up until 1985.