Metallica's infamous album, Lulu, turns seven years old today, Nov. 1. The band took the opportunity to have a little fun with the occasion on Twitter, saying, "Everyone’s favorite album 'Lulu' was released #OnThisDay in 2011. Dare we ask what your favorite song on the album is?" They added a winking-face emoji for good measure.

Lulu is a masterpiece.



Lulu is a collaboration album between Metallica and art rock legend Lou Reed and was the final full-length audio project that Reed contributed to before his death in 2013. "One of the beautiful things about being in Metallica and being a member is to be able to take on challenging projects that I feel and I believe make us a better band," bassist Robert Trujillo said last year. "And the Lou Reed album was definitely a project that set us off on a journey creatively. Love it or hate it, it was definitely something that we enjoyed and that we embraced."

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