Imagine being in the audience for this one…

On this day in 1969, the newly-created Led Zeppelin kicked off a three-night run at the Whisky in L.A. It was only their fifth show in the U.S., and several days before their first album came out. Rotating in the headliner slot was the equally-new Alice Cooper band.

And what did Zeppelin sound like back then? This not-great-quality bootleg recording from the 1/5/69 show should give you some idea. “Babe I’m Gonna Leave You” sounds especially strong (starting around 22:00).