Released in March of 1973, "Houses Of The Holy" features legendary tracks such as "The Song Remains The Same" and "No Quarter" while also showcasing the continuing evolution of the band's signature sound with the reggae-tinged "D'yer Mak'er" and the funk jam "The Crunge". The album has been certified diamond by the RIAA for sales of over 11 million copies.

The seven unreleased tracks on the companion audio disc include rough and working mixes for "The Ocean" and "Dancing Days" that reveal a deeper look inside the recording sessions of these classic songs. Other standout recordings include the guitar mix backing track for "Over The Hills And Far Away" and a version of "The Rain Song" without piano.

The group are releasing both "Houses Of The Holy" and "Led Zeppelin IV" on the same day. Led Zeppelin kicked off their reissue series in June with the release of expanded editions of the band's first three albums - "Led Zeppelin I", "Led Zeppelin II" and "Led Zeppelin III" - each with a companion disc of bonus material.