Back in 1963, John Wayne was shooting Circus World (known as The Magnificent Showman in UK) with Claudia Cardinale and Rita Hayworth.

Duke starred as Wild West circus star Matt Masters in the movie that received mixed reviews and would ultimately be a financial disappointment.

Fans will remember there’s a climatic circus fire scene in the movie, but it ended up being a real-life flaming disaster that burned through 40 sequel feet of the Aranjuez set.

In fact, it was such a close call that Wayne was almost killed during the accident.

John Wayne’s estate shared on Instagram this week: “Today marks the 60th Anniversary of the release of Circus World (1964). When circus proprietor Matt Masters, played by John Wayne, decides to take his show on a European tour, it is beset by problems, while he searches for Lili, the mother of his adopted daughter, who disappeared years before. Did you know? John Wayne sailed his yacht the Wild Goose to Europe in order to make this film.

“Whilst filming a scene where the main tent catches fire, John Wayne was almost killed when the set collapsed. As he was ‘fighting’ the fire, Duke was to be cued by the assistant director when to leave before the set was to collapse in flames.

“Either Duke didn't hear the cue, or the a.d. mistimed it (it was never determined which), but the flaming set began to collapse before Duke got out. He escaped with just a few seconds to spare before the entire set would have fallen down on top of him.”

Wayne was suffering from lung cancer during filming, which he didn’t know at the time.

Duke already had a chronic cough and after the near-fatal fire, he began spitting up blood but continued to chain smoke cigarettes, unaware of the true cause.

Then in 1964 he was diagnosed and had his entire left lung and two ribs removed, meaning he secretly had to rely on an oxygen mask on future film sets that were at a high altitude.