LADY Mary would have been travelling in a Daimler Phaeton, or some such luxurious motor car. My companion and I, however, are tripping across the sweeping gravel driveway, balancing our golf umbrellas and torches with the giddy air of those who’ve developed ideas above their stations.

It is nearly Christmas and Dumfries House, one of Scotland’s grandest stately homes, is dressed for the occasion. To mark the festive season, the house is offering candlelit tours, showing off its unparalleled collection of Chippendale furniture by the light of dozens of candelabra and an impressive Murano glass chandelier.

The 18th-century mansion, which was built by the Adam brothers for William Crichton Dalrymple, the 5th Earl of Dumfries, between 1754 and 1759, sits at the heart of a sprawling 2000-acre estate.

On arrival, there is no reception desk but we are welcomed in the study in front of a roaring log fire before a member of the small team of staff shows us the accommodation.

Our rooms are in the eves of the lodge, up two short flights of stairs. They are decorated in co-ordinating fabrics – rich tartans – so have a similar feel but, while room five has a generous en suite, room six involves a quick hop across the hall to reach the bathroom.

Every comfort is thought of, from hot water bottle to wind-up torch for finding your way around the estate after dark.

I take room five, which is the smaller of the two but with an impressive bathroom featuring a tub you could scrub a hippo in. Although the rooms are compact, as we’re up in the eves we essentially have a whole section of the property to ourselves, including a lower landing with stocked bookshelf and inviting armchair.

The Lodge is designed to encourage visitors to make it a home-from-home and to spend time there. It certainly works. The kettle is immediately on, shoes off and the relaxing begins.

It’s a thought to venture back out again but, of course, we have our candlelit tour and Christmas dinner to enjoy.

Dumfries House has a fascinating history. Built for the Earl, Dumfries House, in Cumnock, East Ayrshire, it later became one of the homes of the Marquesses of Bute.

In recent years, the house was lived in by the Dowager Marchioness of Bute, Lady Eileen, until her death in 1993. When the 6th Marquess died a few months later, the house passed to the 7th Marquess, the racing driver John Bute. Due to the expense of the upkeep of the building, he twice offered it to the National Trust for Scotland: the first time he was refused and the second, negotiations fell through. By 2007, Dumfries House faced an uncertain future with John Bute deciding to auction the property's contents. This caused consternation for preservationists as the furniture remained untouched from an inventory of the House in 1803. But, when no buyers came forward, the Chippendale pieces and others were packed up in preparation for the journey to Christie’s in London to be sold.

At the 11th hour, Prince Charles stepped in by taking out a private loan and bringing together a consortium of charities, government, private individuals and heritage bodies to form The Great Steward of Scotland’s Dumfries House Trust, which purchased the estate for £45m and prevented dispersal of the contents.

So last-minute was the intervention, Prince Charles has said in interviews that the vans heading to Christie's were pulled over at the side of the motorway at 1am and ordered to about-turn.

The Trust’s plan was to maintain and develop the house as a visitor attraction while also providing a model for heritage-led regeneration in what is an economically deprived part of Scotland.

In 2008 Dumfries House opened to the public for the first time in 250 years and visitors are now able to take guided tours, giving insight into the life and history of the building.

Visitors can also stay on the estate. The Lodge, where we are staying, dates from 1750, and has been converted into a 22-room guest house with adjoining self-catering cottages. If you’ve ever wondered what a B&B run by royalty might be like, this is it. Guests are encouraged to make use of a lounge area and study, garden and courtyard.

A quick walk through the grounds later, we are climbing the stairs to the front of the house where a glass of fizz in the grand entrance hall awaits. If you have ever watched the Downton Abbey Christmas special and wished to be waited on hand and foot in front of festive decorations someone else has taken the time to hang, now’s your chance.

The house, while beautiful in daylight, is stunning when dressed and lit for Christmas. As you would expect from a residence with regular royal visitors, the service is faultless and the attention to detail perfect.

As well as the historical facts and figures of the usual tour, our engaging guide, Alex MacDonald, slips in as many festive references as he can. We see the world’s first Christmas card, set up in the drawing room, and we meet Santa, who has fallen asleep at the Chippendale desk in Lord Dumfries's Study. My companion very nearly leans against a beautifully upholstered Chippendale chair in the Family Parlour – they don’t do ropes at Dumfries House, you’re taken on trust – before guiltily sidling sideways on learning it’s valued at £1.4m. There are 20 of these chairs in the house, along with a bookcase for which one bidder offered £25m. Certainly, Prince Charles caught himself a bargain.

The tour ends in the Tapestry Room where we sing Silent Night in German, accompanied by the tour guide on the piano. (The resident pianist is away.) The house well and truly explored, we sit for a three-course Christmas dinner with silver service as the resident harpist plays us through the meal. My companion has quite tricky dietary requirements but is amply catered for, thanks to a creative chef.

After a night’s rest and a hearty breakfast we take some time to explore the estate. There is plenty to see, particularly for families: miles of scenic woodland walks, an arboretum containing more than 500 trees, a visitor centre, The Adam Bridge, The Chinese Bridge, adventure playgrounds, a maze, the Rothesay Garden, the A-listed Temple Gate and the five-acre Queen Elizabeth Walled Garden, which is one of the largest in Scotland.

If we had been hungry after breakfast, we could have eaten in The Woodlands Restaurant or the Coach House Cafe.

The restaurant sits alongside a traditional crafts workshop and hospitality training centre, which are run as part of The Prince's Trust. It's one of several charitable endeavours on the estate, including The Prince's Drawing School, which runs a programme of residences year-round for Glasgow School of Art students.

Youth groups are able to use the Tamar Manoukian Outdoor Centre, which gives young people the chance to take part in activities across the estate. Primary school classes are welcome on the estate to learn about planting vegetables, harvesting and cooking them.

There are also dance and music classes, given by students from the Royal Conservatoire of Scotland, for young people from local towns.

Dumfries House is a busy, vibrant estate with plenty of surprises in store for those newly visiting and its rapid development means there is always something new for repeat visitors.

A walk through the grounds on a bright winter's morning could have you miles from civilisation, despite the M77 making it within easy reach.

"Everything is just perfect," says my companion. Fit for king-to-be, in fact, and certainly fit for a magical start to Christmas.

Catriona Stewart was a guest of Dumfries House Lodge www.dumfrieshouselodge.co.uk

5 Things To Do in East Ayrshire

1. The Scottish Dark Sky Observatory sits on the edge of the Galloway Forest Dark Sky Park and offers an exciting experience for star-gazers. The educational observatory has some of the darkest skies in the UK and two large, impressive telescopes. Visits must be pre-booked www.scottishdarkskyobservatory.co.uk

2. Burns House Museum in the village of Mauchline is set in the Bard of Ayrshire's former home, where he lived during what is said to be his most creative period.

3. If you want to travel beyond Dumfries House's extensive grounds, Dean Castle and Country Park in Kilmarnock offers a fun – and free – day out for families. The top attraction is the 14th Century castle with a collection of historic weapons, armour and musical instruments.

4. Animal-lovers will have a grand time at Blackstone Clydesdales, Cumnock. where it is possible to work, ride or drive the Clydesdale Heavy Horses or meet the Highland Cows, Alpacas and donkeys.

5. Ayrshire Segways, in Auchinleck, offers an alternative way to see the countryside around the Auchinleck Estate.