T4 On The Beach returned to Weston-super-Mare's beach lawns where Dizzee Rascal was the headlining act.
Calvin Harris, who last appeared at T4 in 2007, performed four songs including Acceptable In The 80s and Girls.
Peter Andre was there to perform his new single.
It rained heavily throughout the day.
But the sun did appear towards the end of the show though.
The Gossip were the first act to appear on the main stage.
Florence and the Machine performed three songs, including a cover of You've Got The Love.
The heavy rain caused many to abandon their footwear.
Around 45,000 pop lovers travelled from across the country to attend the event.
Winners of this year's Britain's Got Talent, Diversity, performed. Part of their dance routine included a dedication to Michael Jackson.
Basement Jaxx's performance saw some imaginative costumes on display, such as two people dressed as pandas.
The Saturdays managed to negotiate successfully the slippery stage while wearing extremely high stilettos.
The event also featured a second stage where acts including Little Boots played.
Will Young's performance was when the rain was at its heaviest.
Alesha Dixon, Sohpie Ellis-Bexter and Metro Station also performed.
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