On Aug. 12, 1968, in a small space on Gerrard Street in the west end of London, Jimmy Page, Robert Plant, John Paul Jones and John Bonham played together for the very first time. The first song the band -- which would later be named Led Zeppelin -- tore into was "The Train Kept A-Rollin'," which was a fixture in Page's previous band, the Yardbirds.

According to Led Zeppelin's website, the chemistry was instant. "We first played together in a small room, a basement room," recalled Jones. "There was just wall-to-wall amplifiers and a space for the door -- and that was it. Literally, it was everyone looking at each other -- 'What shall we play?'" As they kicked into gear, "the whole room just exploded," said Jones.

Even though the band was still known as the New Yardbirds at the time, they were off to a strong and fresh start. And everyone there felt the electricity. "I remember the little room -- all I can remember it was hot and it sounded good," said Plant. "Very exciting and very challenging really. It felt like we’d found something that we had to be very careful with because we might lose it. But it was remarkable, the power.”

The band would play its first concert on Sept. 7; the name change would come a little more than a month later, on Oct. 14. "Exciting is the word," Page said about that first jam session, "At the end, we knew that it was really happening, really electrifying."

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