The 1975 album Billy Corgan said invented heavy metal. But even he admits it isn’t actually metal

Billy Corgan says Led Zeppelin helped lay the groundwork for heavy metal, and singled out the band’s 1975 album *Physical Graffiti* for its darkness and weight. He acknowledges that Zeppelin are difficult to classify as metal, but argues their sound offered blueprints that later musicians continued to use.

Corgan particularly praised “In My Time of Dying”, describing its emotional intensity as overwhelming. He also admired Jimmy Page’s distinctive presence and respected the band’s decision to end after drummer John Bonham died, relating it to his own experience of trying to replace Smashing Pumpkins drummer Jimmy Chamberlin. Robert Plant has also named *Physical Graffiti* as his favourite Led Zeppelin album.