The biggest music festival debut in the United States this year may very well be Rock in Rio, which will head to Las Vegas for two huge weekends in May. The festival added more firepower to a show already featuring headlining sets from Taylor Swift, Bruno Mars, Metallica and more. Sam Smith, Charli XCX, Jessie J, Bleachers, Tove Lo, Empire of The Sun and Echosmith are the latest performers to be added to the lineup as of Tuesday (from Billboard). 

The setup is different than Coachella and Austin City Limits in that the lineups are totally different between the two weekends. The first will put the "rock" in Rock in Rio, featuring gigs from Metallica, Linkin Park, No Doubt and others, including a slew of hard rock/metal acts on Sunday. The second weekend will shift to a more pop-friendly setup featuring Swift, Mars and others including Ed Sheeran

The new lineup details come just as Bonnaroo released its lineup via a social media campaign on Tuesday, reflecting the continued lineup battles between various festivals (although Rock in Rio seems to be going for a different audience than more alt-oriented lineups). 

Tickets go on sale January 20. You can check out the day-to-day lineups below: 

May 8
Main Stage: No Doubt, Maná, The Pretty Reckless
Sunset Stage: Foster the People, Gary Clark Jr, Bleachers, Saints of Valory

May 9
Main Stage: Metallica, Linkin Park, Rise Against, Hollywood Undead
Sunset Stage: Deftones, Sepultura (feat. Steve Vai), Coheed and Cambria, Of Mice & Men

May 15
Main Stage: Taylor Swift, Ed Sheeran, Echosmith, Ivete Sangalo
Sunset Stage: Jessie J, Charli XCX, Tove Lo, James Bay

May 16
Main Stage: Bruno Mars, Sam Smith, Empire of the Sun
Sunset Stage: John Legend, Joss Stone, Magic!, Mikky Ekko

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