In July 2016, David Gilmour performed two concerts in Pompeii -- a historical return to the site where Pink Floyd had recorded a legendary concert film in the ancient Italian city over a four-day period starting on Oct. 4, 1971. The guitarist added one element this time around that was missing from the earlier show: an audience.

In early 1971, French movie director Adrian Maben came to the group with the idea of making an anti-concert film -- a reaction to the popularity of features like Woodstock, Monterey Pop and Gimme Shelter. The twist he had in mind was to do something without an audience, which could pull focus away from the band onstage.

“I felt, at the time, that we'd had enough of concert films,” Maben told a Russian Pink Floyd fan site. “So the main idea of the film was to do a sort of anti-Woodstock film, where there would be nobody present and the music and silence, and empty amphitheater, would mean as much, if not more, than a million crowd.”

Having visited the Amphitheatre of Pompeii on vacation, Maben thought it was the perfect spot to capture the essence of the group, which was between their Syd Barrett and The Dark Side of the Moon eras. They just recorded their sixth album, Meddle, and that record’s epic closer, “Echoes,” would be a highlight of Pink Floyd: Live at Pompeii, which was released in 1972.

The band's music took '60s psychedelia to brand new levels, but they had pulled further away from the pack with Meddle, a transitional work in which Gilmour’s confidence rose and his contributions started to mesh perfectly with Roger Waters' songwriting. The Pompeii gig, in other words, arrived at the perfect time.

The logistics to making the film happen weren’t as difficult as you'd expect. The hardest part might have been the limits of travel and technology at the time. To get all of its equipment to Pompeii, the band had to rent moving trucks to get its gear to the site. This was before the Channel Tunnel, so the trek took a few days.

When Gilmour, Waters, Rick Wright and Nick Mason arrived by plane, the first “major crisis,” according to Maben, was underway: There was no electricity at the site. Having been built sometime around 70 BC, the amphitheater wasn’t exactly fitted with electrical outlets, so Maben basically had to run an extension cable from the venue to a church in the city center, an issue that took three days to solve.

From that moment on, things went smoothly. Maben told the Pink Floyd website Brian Damage in 2003 that the only staunch request the band had was there was to be “no playback” -- it had to be an entirely live recording. The director credited the amphitheater's natural acoustics with the superb sound heard in the movie. He also managed to keep it audience-free, except for a handful of curious local kids who stayed out of the frame.

Still, for what would appear to be such an enormous undertaking, the initial theatrical release in September 1972 yielded just 60 minutes of footage, and that included the band recording the early stages of The Dark Side of the Moon at Abbey Road studios. Subsequent versions stretched the running time to 92 minutes with the addition of interviews and images from NASA’s Project Apollo.

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