If Scotland is failing to cash in on potential filming opportunities thanks to Outlander, the same cannot be said for the country’s tourism industry.

Historical sites are braced for a fresh wave of Outlander mania as the time-travelling period romp returns.

The hit series, set in 18th Century Scotland, is set to hold its season two premiere at the American Museum of Natural History in New York tomorrow, but the ripple effects will be felt in remote corners of Scotland which have become major international visitor attractions in the wake of the show’s global success.

Although UK viewers have to pay to view Outlander on the internet steaming site, Amazon Prime, it has garnered a huge cult following here with an even more enthusiastic following among foreign fans enamoured by the romantic depictions of Jacobite-era Scotland.

VisitScotland jokingly tapped into Outlander tourism with its “kilty pleasures” marketing campaign to coincide with the season one DVD launch last year, but the tourism windfall is no joke.

Scottish locations featured in the show, including Preston Mill and Doune Castle near Stirling, are reporting a surge in visitor numbers.

Malcolm Roughead, chief executive of VisitScotland, said: “The phenomenal success of series one of Outlander had an amazing impact on a number of attractions, tours and other tourism businesses throughout the country, with Scotland’s scenery, culture and heritage showcased to viewers worldwide. Research suggests around 40 per cent of visitors to the UK are inspired to visit locations after seeing it on film or on television so, with even more Scottish historic buildings and landscapes on show in series two, we are looking forward to seeing the ‘Outlander Effect’ continue.”

For the uninitiated, the show starts out in 1945, when former World War II nurse Claire Randall and her husband Frank are visiting Inverness, Scotland.

While exploring the fictitious Craigh na Dun standing stones near Culloden (they are actually the Callanish Stones on Orkney), Claire faints after she touches the highest stone, and awakes to find herself in the middle of what appears to be a skirmish between Redcoats and rebel Scottish Highlanders.

Rescued from an attack by Frank’s sinister double, Redcoat Captain Jonathan “Black Jack” Randall, she uses her medical training to help the injured Scotsman Jamie Fraser – played by Heughan.

From there expect a sort of Mills & Boon meets Highlander epic, with a splash of Tudors-esque approach to historical detail and sex.

But if the series is fiction, its impact on tourism is real.

Between September 2014 and September 2015, Falkland – the Fife village which portrays 1940s Inverness in the first episode – experienced a 12 per cent spike in visitor numbers.

Preston Mill, which features as a backdrop in several scenes, recorded a 26 per cent surge year-on-year, while Culloden visitor numbers rose 19 per cent.

Historic Scotland also reported a 44 per cent surge in summer visitor numbers at Doune Castle, which has a starring role as Castle Leoch, and is now hiring extra tour guides and staff to cope with the influx.

At Blackness Castle in West Lothian, which stands in for the stronghold of Fort William, tourist visits were also up 31 per cent.

The global popularity of the series is also leading to an increasing number of tours tailored to Outlander fans.

Catriona Stevenson, of Slainte Scotland tours, has seen demand for her Outlander tours triple since they launched last year.

She said: “I’ve had people from Israel, Japan, Singapore, Germany, Spain, Brazil, Chile, I had a girl from Peru, obviously US and Australia. I took my cousin who was over from South Africa and when she went back to South Africa it had started showing on TV there.

“It’s growing everywhere. I had Germans on Saturday and French Canadians the other day.”

The history enthusiast devised the trips, which include either a nine-hour day tour costing £59 per adult or an Outlander cruise from South Queensferry, after hearing visitors discussing the show.

At first she had no idea what it was but, after binge-watching it online, she is now a fan herself.

She added: “I’m getting people who are visiting Scotland just because of Outlander. So they might not necessarily go on an Outlander tour, but they’re telling me that Outlander gave them the push to visit.

“We had a woman on the Loch Ness tour who was travelling with family and she said she’d have loved to do the Outlander tour, but she thought it might have bored them a bit.

“But she was in Scotland because of Outlander, and a lot of places are seeing that effect.”

Stevenson added that Outlander is also giving neglected corners of Scotland a chance to shine.

“I think [some tourists are] so surprised that the sets are actual historical buildings so it’s a kind of double whammy really – I recognise this from Outlander, but it’s such a pretty place. Like Falkland: people get there and they’re like ‘wow’.

“That’s the real benefit that Outlander has given – a lot of these smaller, less known places are getting a lot more attention.

“A lot of other tour guides are doing Outlander trips now too, because they’ve noticed it’s something that people are interested in so they want to tap into it.”

She added that films sites like Blackness Castle and Doune Castle were seeing tours and visitor numbers rocket thanks to Outlander.

She said Doune was “seeing a massive increase in numbers, I think they just hit 70,000, and they’re taking on extra staff as a result. It’s nice to see the economy enjoying some kind of effect from it.”