SAM Heughan, the lead star in Outlander, has said Scotland has been "late" to capitalise on the "Outlander effect".

Heughan told Radio Times that tourism bosses haven't taken the full advantage of the flood of tourists who have come to Scotland to explore the locations of the hit series. 

Many of the filming locations in the show have seen a spike in visitors due to the show's popularity, including Doune Castle – which tripled its visitor numbers from 38,081 to 124,341 – and Blackness Castle. 

The National: Outlander 2014  Claire Randall (Caitriona Balfe), Jamie Fraser (Sam Heughan)

He cited a surge in "unofficial" tour operators who marketed themselves as guides around the areas shown on the screen and recommended tourism boards do more to cater to the demand. 

Last year, the show's filming locations were reported to have had a 67% increase overall in visitor numbers as a result of the series, with interest from both Scottish people and those visiting from further afield. 

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Heughan said: “I think Scotland was actually kind of unaware of what’s been happening here for many years, I think we were under the radar a little bit. I think finally they’ve realised, I think Scottish tourism has obviously risen dramatically.

“Doune Castle, that played Castle Leoch, home to the Mackenzie clan in the show, was up 600% in their tourism numbers, there’s so many now unofficial Outlander tours, there’s vast tourism here, so I think people are really realising and the Scottish government as well.”

He said the Scottish Government were "maybe a little late" to jump on the buzz. 

Series 5 of Outlander will be available in the UK from February 17 on Amazon Prime.