Coachella's first weekend had no shortage of surprises.
Those unexpected moments incited quite the buzz on Twitter, where attendees in California and people watching live streams from afar on YouTube posted more than 1.6 million tweets about the action from April 11 to April 14.
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Here are the top five most-tweeted moments based on Twitter analytics:
1. Beyonce dances with sister Solange.
Out of nowhere, Beyonce returned to Coachella for the first time since 2010 when on Saturday she made an energetic cameo during her younger sister Solange's set.
The Knowles siblings, like sisters enjoying music in their bedrooms, danced in unison to "Losing You" while a stunned audience cheered on the antics.
2. Justin Bieber joins Chance the Rapper.
In another unscheduled cameo, Chance the Rapper brought Justin Bieber onstage to perform "Confident." Bieber posted a snippet of it on Instagram.
3. Lana Del Rey debuts 'West Coast.'
"Video Games" singer Lana Del Rey used her stage time at Coachella to debut "West Coast," a slow-paced tune from her upcoming third studio album, Ultraviolence.
The 27-year-old artist's appearance and premiere helped her become the most-mentioned musician at Coachella this year so far, according to this ranking from Twitter.
Surprised? These were the most-mentioned artists at #Coachella during the first weekend pic.twitter.com/VDL9TbBujG
— Brian A. Hernandez (@BAHjournalist) April 15, 2014
4. Jay Z comes out during Nas' set.
Beyonce's husband, Jay Z, also made a surprise appearance, taking the stage with rapper Nas to perform "Dead Presidents II."
Jay Z previously headlined the music festival in 2010, at one point unexpectedly bringing out Beyonce to perform "Forever Young" together.
5. Outkast reunites as headliners.
All eyes were on Outkast at Coachella when André 3000 and Big Boi performed together for the first time in seven years. So it was only fitting that, like caged animals at a zoo, the hip-hop headliners started their set inside a cube that displayed nifty, ever-changing designs.
Big Boi and André 3000 also each had time alone onstage to spit out songs from their solo careers. They sprinkled the set with cameos from Janelle Monae and Future.
Coachella's most-shared photos
Twitter also tracked which pictures, below, got the most retweets and favorites.
BONUS: The 12 Most Coachella Things to Happen at Coachella
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