Queen looks back on its first "Greatest Concert" - Hyde Park in 1976

Before Live Aid 1985, there was Live in Hyde Park 1976.

Queen explores its first "greatest gig" in the tenth installment of its ongoing Queen The Greatest YouTube series, celebrating the iconic British rock band's golden anniversary.

Following the riotous success of 1975's A Night at the Opera, Queen wanted to say thank you to its rapidly growing fan base in spectacular fashion, with a free concert at a London rock and roll landmark.

Guitarist Brian May said in one interview at the time that the concert took over two months to plan, and due to concerns over a drought, the band couldn't be sure the show would actually go on until "the last moment."

Despite the hand-wringing — and after contributing £50,000 of their own money — Queen took the stage on September 18, 1976, and rocked an audience of 150,000 - 200,000 strong for more than an hour and 20 minutes.

May recalls "getting very, incredibly, naturally kind of high before going on because although we’d played to large audiences before, this is London, it’s our home and that’s something different.”

Despite the extraordinarily large audience, the concert was peaceful with only four arrests made over the 9-hour gathering. According to May, there would have been four more arrests had Queen gone out for an encore.

"It was very strange," he said. "Because I think people got nervous of the crowd, and people worried whether it could be controlled in the dark and things like that… Apart from things like that it was great.”

The members of the band were shuttled away from the venue and the crowd was disbursed to the relief of local officials.

The Hyde Park concert was filmed and the footage was later used in the music video for "Somebody to Love," Freddie Mercury's favorite Queen song of all-time. Looking back, May says the gig showed Queen how far it had come in its home country.

“I remember thinking…gulp…you know, we’ve carved out a place around the world, but England doesn’t really think we’re that cool. It was packed beyond belief, and it was really like coming home to a sort of hero’s welcome.”

Watch the full Queen the Greatest episode via the player above!