Released in the U.S. on this day in 1969, Led Zeppelin is the eponymous debut album by Led Zeppelin. The album was recorded in September and October 1968 at Olympic Studios, London shortly after the band's formation. It contains a mix of original material worked out in the first rehearsals, and remakes and rearrangements of contemporary blues and folk songs. The sessions took place before the group had secured a recording contract and were paid for directly, and took 36 hours and less than £2,000 to complete. The album showed the group's fusion of blues and rock, and their take on the emerging hard rock sound was immediately commercially successful in both the UK and US. Although the album was not critically well-received when first released, critics now regard it as one of the greatest debut albums in rock history. Since it's debut the album has gone on to sell over 10 million copies. Happy 51st Anniversary!