Physical Graffiti was later certified 16× platinum in the United States by the Recording Industry Association of America (RIAA) in 2006, signifying shipments of over eight million copies in the US.

However, these sessions came to a halt quickly and the studio time was turned over to Bad Company, who used it to record songs for their debut album.

"[10] As with previous sessions at Headley Grange, the informal atmosphere allowed the group to improvise and develop material while recording.

Bonham was a driving force at the sessions, regularly suggesting ideas or the best ways in which a complicated arrangement could be played successfully.

[12] Additional overdubs were laid down, and the final mixing of the album was performed in July 1974 by Keith Harwood at Olympic Studios, London.

In particular, "In My Time of Dying", "Trampled Under Foot", "Kashmir", "Ten Years Gone", "Black Country Woman", and "Sick Again" became regular components of the band's live concert set lists following the release of the album.

[21] "Houses of the Holy" was recorded as the title track for the album of the same name in May 1972 at Olympic Studios with Eddie Kramer engineering.

The song went through several arrangement changes before arriving at the version heard on the album, with the group rehearsing various different ideas and arguing about the overall style.

Bonham decided the track was too "souly" and rearranged it into a funk style, suggesting that Page should play a guitar riff throughout in place of chords.

[26] "Bron-Yr-Aur" was a solo acoustic piece by Page, named after the cottage where he had composed and arranged much of Led Zeppelin III with Plant.

[27] "Ten Years Gone" was mostly composed by Plant about an old love affair, and was combined with an instrumental piece from Page, featuring overdubbed electric and acoustic guitar parts.

[27] Plant wrote the lyrics after reading a news headline entitled "Nuclear Damage Test Threat" and wondered why there seemed to be little peace and love in the world.

Unlike some of the other tracks recorded at the 1974 Headley Grange sessions, it was straightforward to arrange, with the group building the song around the riffs.

[27] "Boogie with Stu" was a jam session with Rolling Stones pianist Ian Stewart based around the Ritchie Valens song "Ooh My Head".

[30] "Black Country Woman" was recorded in the garden at Stargroves in 1972 for Houses of the Holy, as part of the group's desire to work in "off the wall" locations outside a traditional studio environment.

[32] The album was originally released with a die-cut sleeve design depicting a New York City tenement block, through whose windows various cultural icons could be interchangeably viewed.

[34] (The front doorway and stoop at 96 St. Mark's Place is also the location used by the Rolling Stones for the music video promoting their single "Waiting on a Friend", from their 1981 album Tattoo You).

The album was a commercial and critical success, having built up a huge advance order following the delayed release date, and when eventually issued it reached No.

[49] The group debuted several songs from Physical Graffiti live at a warm-up gig in Rotterdam, Netherlands, on 11 January, a week before the US tour, which lasted until 27 March.

Tickets for the shows sold out within four hours, described by promoter Mel Bush as "unprecedented demand in the history of rock music", so a further two dates were added.

[50] The shows attracted rave reviews, and critics noted the band enjoyed playing the new material on Physical Graffiti more than the older songs.

He speculated it could be the group's best work to date, saying "the album's tonal density is absolutely the toughest, most downright brutal I've heard all year".

[52] In March 1975, Billboard magazine's reviewer wrote: "[Physical Graffiti] is a tour de force through a number of musical styles, from straight rock to blues to folky acoustic to orchestral sounds.

"[53] Similarly, Jim Miller stated in Rolling Stone that the double album was "the band's Tommy, Beggar's Banquet and Sgt.

[57] Plant later felt that Physical Graffiti represented the band at its creative peak, and has since said that it is his favourite Led Zeppelin album.

[58] Page has also said the album was a "high-water mark" for the group, and the creative energy from jamming and gradually working out song structures together led to some strong material.

[59] Reviewing the album for BBC Music in 2007, Chris Jones described it as "a towering monument to the glory of Zeppelin in their high-flying heyday".

However, it was done without input from the band, and the first pressing accidentally edited off the studio banter at the end of "In My Time of Dying" (later fixed on repressings).

[80] An extended remastered version of Physical Graffiti was reissued on 23 February 2015, almost exactly forty years after the original album was released.