The Data Behind the Ur-Physical Graffiti

Despite listening to Led Zeppelin for over twenty years, I just learned this week that their sixth studio album, Physical Graffiti, was actually two-thirds original material and one-third outtakes from previous albums. Apparently the band recorded three sides’ worth of material for the album but didn’t want to trim anything; so instead they made it a double album by sprinkling outtakes across all four sides.

There were eight original tracks recorded for the album and seven outtakes added. Three outtakes came from each of the previous two albums, Houses of the