"The Ocean" is a song by English rock band Led Zeppelin, from their 1973 album Houses of the Holy. "The Ocean" refers to the sea of fans seen from the stage at Led Zeppelin concerts, to whom this song was dedicated.

The intro and chorus (the main riff) are in 15/8; the song is in a 4/4 beat in the verses and the latter part of the song. The voice on the intro is drummer John Bonham referring to the takes: "We've done four already but now we're steady, and then they went 1, 2, 3, 4!" They had tried to record it four times previously but could not get it right, prompting the chant.

At approximately 1:37–1:38 and again at around 1:41, a telephone can be faintly heard ringing in the background. Some speculate that this was intentional — the sheet music (printed after the fact) that accompanies the CD box set has the word "ring" printed twice above the percussion tab of this song. Others are of the opinion that while Led Zeppelin recorded the song a phone was accidentally captured in the mix. Eddie Kramer, present during the recording of Houses of the Holy, states, "It's entirely possible. [The song was] done in a house." He also states, "I don't remember there being [a phone ringing]," implying that it was an accident. There is also a noise heard about 1:59 which sounds like someone pronouncing "c" as in "catch". This occurs again at about 2:12. Jimmy Page remarked:

"I'm thrilled the records are recorded in such a way that the hi-fi quality, even though it's tough… you can hear detail on it because that's what you're supposed to do. It was supposed to be something whereby you could hear everything that was going on."

In the last line, the "girl who won my heart" refers to Robert Plant's daughter Carmen, (born 21 November 1968), who was three years old at the time of recording. In concert, Plant always updated the lyric to reflect her current age, as captured on the Led Zeppelin DVD which features a performance of the song at Madison Square Garden in 1973. During this performance, Plant sang the third verse, which starts with "Sitting round singing songs 'til the night turns into day" as the second verse and sang the second verse at the end of the song. The band first played the song live on their 1972 U.S. concert tour and it remained as part of their performances until their 1973 U.S. tour. It was deleted from the set list thereafter.

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