It's hard to believe that it's been a whole decade since Adele's second album '21'.

The Londoner's 2011 album celebrated its 10th birthday yesterday, and Adele took to Instagram to mark the occasion with a post.

'21' was the album that set Adele up for superstardom on a global level, with songs like 'Someone Like You', 'Rolling in the Deep' and 'Rumour Has It' on the tracklist. It went on to top the charts in 30 countries, and was the best-selling album for both 2011 and 2012. The album is reported to have sold over 31 million copies worldwide.

"Well I never! Happy 10 years old friend!," she wrote on Instagram. "It’s crazy how little I remember of what it was like and how I felt a decade ago. But Thank You from the bottom of my heart for letting us into your lives and letting me be a soundtrack to some of it x"

 

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However, she did not respond to fans in the comments who were asking about her forthcoming fourth album - which was due for release in 2020.

Earlier this month, comedian and friend of the singer Alan Carr hinted that the album will be released in February, but there has been no official confirmation.