"Rock of Ages" is a song by Def Leppard from their 1983 album Pyromania. When released as a single in the United States, the song reached number 16 on the Billboard Hot 100 chart and number one on the Top Tracks rock chart.

It begins with a German-like nonsense phrase, "Gunter blieben glästen globen", introduced by Mutt Lange, who is of German descent. According to the official Def Leppard FAQ,

These four words that you hear at the start of "Rock of Ages", mean nothing, though the band sometimes jokingly claims it means "running through the forest silently". It's actually just German sounding gibberish, said by producer Mutt Lange during one of the later takes of the song. Lange was a perfectionist and would often do dozens & dozens of takes, and after repeatedly beginning so many with the standard count, "One, two, three, four" he simply started saying nonsense words instead, the band liking this one so much that they included it on the album.

According to Google Translate, the words translate to "Gunter remained glazed globes."

This phrase was later sampled in "Pretty Fly (for a White Guy)" by the Offspring as well as "Call Me What You Like (If You Like Rock-N-Roll)" by Puffy AmiYumi. This was also sampled in a parody of the song, "Rape Rock of Ages", by shock rock band the Mentors.

According to the liner notes of the compilation release Rock of Ages: The Definitive Collection, the band was at a recording studio when lead vocalist Joe Elliott stumbled upon a hymn book left by a member of a children's choir that had just used the studio. In the book, he saw the words "Rock of Ages", which prompted him to write the lyrics of the song.

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