Look inside Hillsborough Castle: how a £24m project helped turn the royal residence into a must-see attraction

The year was 1925, when the basic necessities for the landed aristocracy were luxuries beyond the wildest dreams of the majority in the recently partitioned state of Northern Ireland. And so the first refurbishment of the draughty old house in the 20th century took place, only to be undone by a fire started by the proximity of a lit cigarette and a half-mast flag on the roof in 1934.

Since then the Queen's official residence here has undergone several interior facelifts and modernisations at the hands, primarily, of Tom King and Peter Mandelson, former lodging Secretaries of State. But, as noted by those present for the signing of the 1985 Anglo-Irish Agreement, the Good Friday Agreement negotiations in 1998 and the talks leading to the 2010 Hillsborough Agreement, the "dull and predominantly beige" castle interiors were not the most inviting.

Roll on a couple of decades, however, and the building once hailed as "the grandest house in Co Down" has been restored to its former, more colourful glory by Historic Royal Palaces (HRP), the independent charity which looks after the Tower of London, Hampton Court Palace, the Banqueting House, Kensington Palace and Kew Palace. Open to the public from April 18, tours of the castle will take in the beautiful 110-acre grounds and enormous walled garden, where an abundance of vegetables are growing for use in the new visitor centre's cafe.

The organisers of the £24m project want to attract visitors of all ages and backgrounds to the estate, which has hosted historical figures from Benjamin Franklin and Eleanor Roosevelt, to celebrities Cilla Black and Paul O'Grady down through the years. And while visitors are naturally compelled to step back in time within the castle walls, the cultural activities to take place therein are taking on a distinctly modern slant.

The Irish language will be given due prominence, according to Dr Christopher Warleigh-Lack of HRP (above), and the tours will include an LGBT-themed foray.

"We'll be looking at alternative histories," says Dr Warleigh-Lack, HRP's senior curator. "Peter Mandelson lived here with his boyfriend, for example, but gay history tends to be hidden history. We work very closely with Queen's University and Ulster University to research our tours."

The official en suite bedroom of the Secretary of State, used as an office in recent years, will be open to the public. It will feature Mo Mowlam's bulky old television set and furnishings from Mandelson's time here.

It is a surprisingly spare and austere room, resembling a 1930s college professor's living quarters, with plain moss-green bedding and dreary mahogany furniture.

By contrast, the bedrooms allocated to contemporary royal staff, such as ladies-in-waiting, offer elegant five-star luxury. Situated at one end of the 'royal corridor', they (and the locked royal chambers) are out of bounds to the public, but Dr Warleigh-Lack allowed a sneak peek into one of them - a bright, comfortable Georgian-style suite that was used by Mowlam's young godson.

"Mo was fond of her bath and often wandered wrapped in a bath towel - legend has it that it once dropped while she was in conversation with someone passing through the wing," says Dr Warleigh-Lack, who makes an entertaining guide.

"Her godson was a frequent visitor. He enjoyed rollerskating along the floors, which were slippy back then. We had to poke around behind the radiators to find the original wood flooring, pre the 1934 fire, for the restoration."

Hillary Clinton got on well with Mo during her visits to Hillsborough, and a glamorous photograph of her younger self has pride of place in Lady Grey's Study. After Mo's death from cancer in 2005 some of her ashes were scattered in the castle gardens. Her tenure is recorded in several framed photographs, one of which captures George Bush and Tony Blair in private conversation in Lady Grey's Study in 2003, in the early days of their joint invasion of Iraq.

Mowlam was very fond of this calm, peaceful room, named after Lady Grey of Naunton, Esme Burcher, wife of the last governor of Northern Ireland, from 1969 to 1973.

It was used as the Sinn Fein office during the peace talks that culminated in the Hillsborough Agreement of 2010. Chief negotiators Gerry Adams and Martin McGuinness are pictured sitting on a castle windowsill in another framed photo in the Red Room, so called because of the resplendent silk wall panels in deepest ruby which adorn its walls.

HRP has replaced the wall panels in both the Red Room and the (emerald green) Throne Room as part of their 're-presenting', as it refers to it, of the castle interiors. It started work in 2014, completing the State Entrance Hall, Ante Room and Red Room by 2017, with new decorative schemes, furniture and paintings reflecting the history of the castle and the village of Hillsborough.

In the Ante Room, the most recent signatures in the visitors' book are those of the Duke and Duchess of Cambridge, from their visit in February. William's is an unadventurous squiggle; Kate's is bigger, straighter and more authoritative.

The imposing Throne Room, State Drawing Room, State Dining Room, Lady Grey's Study and mint-green Stair Hall were completed in the winter of 2018 with the support of the Heritage Lottery Fund. The historic Richhill Gates have also been restored, as well as the mechanism of the Courthouse clock.

A full-time conservator is now in place, responsible for over a thousand pieces of art and furniture, ranging from a Nollekens' bust of former estate owner Wills Hill, on loan from the local parish church, to Mowlam's television set.

One of the conservator's jobs is to maintain more than 40 clocks all over the castle, keeping them wound up to the correct time.

The most welcoming room in the house is the State Drawing Room, which has been redecorated in warm pastels favoured by Queen Elizabeth, The Queen Mother.

A replica of one of her hats - a sky-blue floral confection - sits among royal family photographs, which include a priceless black-and-white shot by Cecil Beaton of a very young Princess Anne treading on the Queen's coronation robe.

In contrast to the more formal art in the Ante Room and State Entrance Hall (which includes a portrait of a young King Billy and a more mature King James II), an unpretentious watercolour of the Mournes by Prince Charles is among the contemporary art on display in the spacious drawing room, along with a bust of Seamus Heaney and an FE McWilliam sculpture.

The drawing room leads into the private sitting room where the Queen famously greeted Mr McGuinness in June 2016.

The original landowners of the castle's site, incidentally, were the Magennis clan; McGuinness is a derivative of the name (the castle - essentially a Georgian country house squashed into a village setting - was built in the 18th century for the Hill family, Marquesses of Downshire, who owned it until 1922, when the estate was sold to the British Government for £24,000).

The Drawing Room's elegant French windows open onto the south terrace and gardens, where the Queen hosts her garden parties. A dedicated team of 16 gardeners and volunteers are working continuously to restore and maintain these gorgeous grounds, which contain their own hydro-electricity system.

Landscape designer Catherine Fitzgerald (who is married to actor Dominic West) acted as consultant for the restoration of the gardens, which run to almost 100 acres at the castle, with a further 10 across the road, by the forge. Having been brought up at the historic Glinn Castle in Co Limerick, Ms Fitzgerald had a natural affinity for the Hillsborough project.

Prince Charles is also fond of a stroll along the numerous river paths and the atmospheric Yew Tree and Moss Walks. His involvement in the design of the restored gardens is not confirmed by the discreet HRP representatives, but there is a striking similarity to Highgrove in certain elements, such as the Walled Garden.

The most ambitious project to date at the estate, this four-acre space dates back to the 18th century, when it was first used to produce fruit, vegetables and flowers for the house. The produce was later sold to local traders.

Now, with the help of the Prince's Trust volunteers, HRP is restoring the site to create a working and productive kitchen garden, complete with dipping pond, crop rotations, seasonal produce, potting sheds, herbaceous borders and an apple orchard.

Meanwhile, the courtyard at the lower end of the estate has been redeveloped into a Welcome Centre, with facilities for schools and groups.

A number of exciting discoveries have been made in this area, including the remains of early 18th century pineapple houses or pineries, and original hot house walls.

According to Dr Warleigh-Lack, these may be one of the earliest sets of large greenhouses to be constructed at a private house in Ireland.

Most of the fresh organic vegetables produced on the estate will be put to delicious use in the new cafe in the recreated stable yard. This area, built in the 1780s at the upper end of the estate, will incorporate a shop and numerous facilities for visitors.

The first floor of the stable yard has been developed into a learning space, providing programmes of activities for schools, families, youth and community groups, as well as talks and workshops for everyone.

And for those hoping for a nod to the late Princess Diana, who visited the castle, she will feature in a Downshire Gallery Hall of Mirrors, currently under construction near entrance, which will reflect 400 years of history at Hillsborough.

"This is just the start of our ambitious project. Last year we also took over management of the Hillsborough Fort and Courthouse buildings, where conservation work has already begun," Dr Warleigh-Lack concludes. "We're reopening the doors of Hillsborough Castle for everyone to explore the stories of this extraordinary place and take part in its inspiring new future."

Hillsborough Castle is open to the public for tours from April 18. HRP has built a new car park at the lower end of the estate,. The castle itself is fully wheelchair accessible. See www.hrp.org.uk / Tel. 028 9268 1308