Viewers will recognise a number of iconic Edinburgh landmarks during scenes in Avengers: Infinity War, one of its directors has revealed.

Joe Russo confirmed Waverley Station, the Royal Mile and St Giles Cathedral would all feature heavily in a ten-minute action sequence near the start of the Marvel blockbuster.

Filmed during night shoots, the director said the Gothic backdrop of the Scottish capital's Old Town created the "right tone" for the scenes.

He also warned fans the film would be "intense", describing it as the "culmination" of the 18 films in the Marvel cinematic universe to date which began with Iron Man in 2008.

The hotly-anticipated superhero crossover, which spent weeks filming key scenes in Edinburgh and St Abbs in the Scottish Borders, is due out on April 26.

Scarlett Johansson (Black Widow), Chris Evans (Captain America), Elizabeth Olsen (Scarlet Witch), Paul Bettany (Vision), Chris Hemsworth (Thor) and Mark Ruffalo (The Hulk) are all believed to have filmed scenes in Scotland.

Avengers: Infinity War will see intergalactic warlord Thanos attempt to collect the powerful infinity stones in order to wipe out half of all life in the universe.

Earth's heroes will team up with the Guardians of the Galaxy on-screen for the first time in the Marvel series in an effort to defeat the villain.

Marvel's latest film follows off the back of the box office-smashing Black Panther.

Speaking to STV News, Mr Russo told fans to "expect a lot" from the new Avengers film, the third after Avengers: Age of Ultron in 2015 and the original Avengers film in 2012.

"It's a very, very big film and if you've been following along with the Marvel universe for the last ten years and you've been emotionally invested in the storytelling, this is the culmination film," he said.

"This is it. This is the ending. This is the final chapter of the book so we pulled out all the stops and we went all-out."

Of the blockbuster's scenes in Edinburgh, he said: "You can expect to see about ten minutes of it the film. You'll recognise quite a lot of it.

"Waverley Station plays a big part in it. The Royal Mile takes a big part in it, underneath the colonnades (where City Chambers is located) and back into (Parliament) Square.

"So if you're from Edinburgh, you'll see it - you'll know it."

He also revealed they filmed shots of the roof of St Giles Cathedral.

The film crew then created a replica of the roof in a warehouse where they recorded a fight scene, meaning in the final cut of the blockbuster it will look like the heroes are battling on top of the historic structure.

While he has a longstanding love of the city, Mr Russo and his fellow director, brother Anthony, chose Edinburgh as a location for the aesthetic qualities it could bring to the film.

"The city fit a sequence my brother and I dreamt of," he explained.

"It had the right tone for what we were looking for.

"We wanted to create a little bit of tension in the sequence in that when you light these buildings at night in the correct way they do take on a Gothic appeal."

Security around the film's plot in order to protect against spoilers went to extreme lengths, Mr Russo revealed, with measures taken including the distribution of fake drafts of the script to cast and crew.

It is because the blockbuster is one of the most-hyped films in recent years, bringing an untold number of Marvel heroes together for the first time.

The threat posed by the film's villain, who has been built up as a force in the shadows since the first Avengers film, is such that speculation of the fate of fan favourites is rampant.

"It is a crazy amount of characters," the director admitted.

"But you're taking all these disparate, really successful franchises and putting them into one film, and that's exciting, that's a challenge and it's a challenge we were up for.

"You work throughout the script process and as you're shooting the movie just to make sure that each character has their moments."

He added: "The movie does get intense. Thanos does not mess around. He's a very scary villain."

But the movie will also have Marvel's trademark levity, particularly with so many much-loved characters meeting for the first time.

"Obviously there's going to be humour when these personalities clash," Mr Russo said.

"Doctor Steven Strange (Benedict Cumberbatch) meets Tony Stark (Robert Downey Jr): these are two very egotistical individuals and they're going to clash over who is in charge.

"One is a man of science, the other is a man of magic, so there's a lot of differences there that they need to overcome while also trying to stop Thanos."

The director also discussed Scotland's distinctive qualities that make it such a viable location for Hollywood studios.

Avengers: Infinity War's use of Scottish locations follows in the wake of a number of blockbusters which filmed scenes in Scotland, including World War Z and Fast and Furious 6.

"Scotland has an incredible topography which is easily accessible and accessible quickly, which is very important for film crews," Mr Russo said.

"You can go an hour that way and be on the coast, you can go hour that way and be at the lochs, an hour that way and you're up in the mountains, an hour that way and you're in Glasgow.

"It really is an accessible location to shoot with incredible infrastructure."

He added: "I really believe that if some sound stages are built here in the proper place and managed properly, that I think Scotland could attract a Star Wars film or a Marvel movie very easily for the duration of their shoot."