Bathed in the soft colours of a stained-glass window, Tracey and Rob Beaton said their wedding vows as the demanding third presence in their relationship loomed all around them.

Just a few months earlier the pretty chapel where they married was an empty shell. It had no ceiling – and no floor either - but there were plenty of cobwebs and plant life sprouting from its many cracks and crevices.

Where the arched window’s colourful peacock patterned glass catches the sunlight now, there was an empty space - if nothing else it matched the gaping holes in the walls.

Just three years ago when the couple arrived at Culdee Castle near Muthill in Perthshire, the entire property was a tumbledown wreck: trees sprouted from exposed innards, the interiors had collapsed, fittings and fixtures were either stripped out or broken.

Some might have turned and ran.

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Instead, having fallen head over heels for the dilapidated 19th century gothic mansion, the pair embarked on a labour of love.

The castle became a demanding mistress requiring them to pour heart, soul and a lot of hard cash - £2.5 million at the last count - into teasing her back to life.

Their wedding was a landmark point in an epic quest to revive the wreck of a building. And there is still plenty to be done.

“It took us three and a half months with conveyor belts and working day and night just to get the ground floor clear so we could find the structure of the building in the first place,” says Tracey.

“To even get to the chapel, we had to repair the roof on the east wing of the castle and restore all the floors and ceilings; five floors from the bottom to the top.

“I’ve never been so poor in my entire life,” she adds. “I suppose we are a little nuts, but it’s a good crazy.”

Indeed, some might wonder why anyone would take on a project that even publicly funded heritage organisations might baulk at.

Yet, they are not the only ones on a personal mission to bring some of Scotland’s most dilapidated ruins back to life.

Last week, the Hawaii-based owner of Cavers Castle, near Hawick – which has a history stretching to the 13th century and was largely destroyed in an 1950s Army demolition exercise - saw her restoration plans finally passed by councillors.

A category B-Listed building that had languished on the nation’s Buildings at Risk Register for years, it caught Julie Sharrer’s eye as she scanned websites from her US home, looking at castles.

Within hours she had rung the sellers’ agent and was planning her Transatlantic flights. And moments after her first glimpse of Cavers Castle, surrounded by a clump of trees, roofless and shattered, she decided she would have it.

She has now overcome a range of issues, including more than 90 objections from locals to the discovery of great crested newts on the site which will now be protected by a barrier.

Soon work will begin, including a new four-storey accommodation wing and landscaping to include the revival of a walled garden linked to Victorian botanist John Scott, and the repair of a Georgian ha-ha.

She is unfazed by suggestions the work could drain her of $1 million or more.

“Nothing they throw out there bothers me at all, we have the finance,” she shrugs. “This is a passion.

“I kept going back to the picture, thinking of what had stood there before. It was just such a majestic thing. I just knew I had to do it.”

The site is steeped in history: the castle was once held by the Balliols, one of its surviving features is an 13th century piscina, while in the early 14th century, it was occupied by an English garrison.

Various redevelopments gave 64-rooms and the appearance of a classical mansion house. But its upkeep began to suffer and by the end of the Second World War a deal was struck that saw the Royal Engineers bombard it with explosives.

Julie, who says she can trace her ancestry to the year 1000 and has a combination of Viking and Swedish heritage, struggles to understand how a country can let aged buildings crumble in the first place.

“It’s a little disappointing that people would let it fall into disrepair to where it had to be demolished and blown up like it was,” she adds.

“That is worse than very sad.”

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It’s estimated that since the 1950s, 250 Scottish castles and tower houses have been restored including around 100 reborn from derelict or ruined state, mostly for private occupation.

Recently entrepreneur Nicole Rudder, whose businesses include an insurance claims company, has spent £235,000 buying B-Listed Garrion Tower, an imposing Victorian pile in the Clyde Valley that was being consumed by nature.

Bought on the spur of the moment, she is now 18 months into turning it into a nine-bedroom hotel, champagne bar, rooftop terrace and restaurant.

While at 16th century Torwood Castle near Larbert, restoration is proceeding at a more restrained pace. Started by a lone owner decades ago, the castle is still open to the elements, without a roof. Restoration is now being progressed by a small community of locals.

For those who battle through bureaucracy and buckets of lime mortar, there are rewards: these days Barholm Castle shines like a glistening white pearl among mature woodlands, overlooking the nature haven of Wigtown Bay where geese flock for the winter and ospreys fish during the summer.

When Dr Janet Brennan-Inglis and her husband John first spotted a signpost at the side of the A75 advertising “Castle for sale”, they didn’t realise they were on their way to becoming accidental castle renovators.

“We didn’t even know there was a castle there,” Janet recalls. “My husband said ‘let’s go now and have a look’. We drove up the road and saw this incredible romantic looking ruin with no roof.

“It took us two years to actually buy it – that’s a common theme among castle restorers,” she adds. “It’s not always easy to buy a castle.”

It cost £65,000 in 1997, but if the price was “a snip”, it would barely scratch the surface of what lay ahead.

Getting permission to begin work to save the A-Listed building took four years – another issue that often rankles castle restorers is the hurdles that have to be overcome as they try to save a building that before they arrived, no-one seemed to want.

To add to the complications, the couple were based in the Netherlands, being paid in Dutch guilders with the exchange rate going in the wrong direction.

“We were in our 40s and thought this would be a place to retire to,” she adds. “Unfortunately, it was becoming a bit too much.

“But there also comes a point quite quickly where it is more difficult to pull out than to just carry on.

“You get sucked in and think you can’t stop.”

Janet recalls one architect’s dire warning. “His report said it could cost as much as £250,000 to put this right and I remember thinking ‘oh my gosh, that’s really quite a lot’.

“In fact, it has cost probably about three times as much.”

Work was finished in 2006.

“I’m happy that we did it,” says Janet, who went on to complete a PhD on castle restoration and is former chair of the Scottish Castles Association.

“It was on the point of collapse - by now it would have gone.

“It was very stressful but it’s a great privilege to be able to have saved it.”

Back at Culdee Castle, built in 1810 for Charles Drummond, whose clan was rewarded for fighting with Robert the Bruce, and bought by the Beatons for £730,000, the honeymoon is over.

Work is starting on the west wing, renovating stone spiral stairs and creating holiday apartments to add to the wedding business and glamping which help fund the restoration.

“We are a fifth of the way in,” adds Tracey. “We’ve done the worst bit.

“But even if we just get the walls and roof watertight before I die, I think I’ll have done a good job.”

 

Want to be king or queen of your own castle? If renovating a castle is too much like hard work, these come ‘ready made’.

On sale for £25million, 17th century Dunbeath Castle in Caithness is a dramatic white walled coastal pile set in 28,000 acres of estate.

More affordable Balbegno Castle in Fettercairn is an A-Listed 16th century tower featuring splayed gunloops and with a Georgian wing. Offers over £780,000.

Fa’side Castle near Tranent, East Lothian, is a historic 14th century castle with unique features including an original stone WC called the Laird's Lug. Offers in the region of £1.7m.

Towie Barclay Castle in Aucherless, Turriff in Aberdeenshire, was bought as a derelict ruin and lovingly restored. The historic seat of the Barclay Clan since 1136, it is on the market for offers over £975,000.

The hammer is set to fall soon – for around £4m - on 15th century Kilravock Castle at Croy, near Inverness. Mary, Queen of Scots and Bonnie Prince Charlie are among its one-time guests.

While 19th century Brough Lodge on Fetlar on the Shetland Islands - population just 69 – is just under £30,000, Community group Brough Lodge Trust wants a philanthropic entrepreneur who’ll commit to investing millions more in creating a knitting heritage retreat.

The ultimate castle restoration, however, must be category A-Listed 19th century former mental hospital, Lennox Castle in East Dunbartonshire. It closed in 2002 and has since been slowly reclaimed by nature.