Led Zeppelin: Standing on the shoulders of giants
In 1975, America's leading promoter Bill Graham, spoke about the unstoppable rise of Led Zeppelin: "This social phenomenon - in no way was it ever in existence in the past and in no way will it ever exist again... the adulation, the massness."
In the space of six prolific years, the English quartet redefined the parameters of rock and become the biggest-selling band on the planet. And, 40 years ago this week - at the very apogee of their popularity - they released one of the decade's most enduring albums, Physical Graffiti - a sprawling, double LP that demonstrated the wide breadth of influences that had made the band so huge.
Running at just over 82 minutes in length, the album featured eight tracks recorded in session between 1973 and 1975 as well as unused material from the sessions for their three previous albums, Led Zeppelin III, Led Zeppelin IV and Houses of the Holy (the latter's title track, confusingly, appears on Physical Graffiti).