Adele doesn't "remember" much from the period in which she created '21'.

The 'Set Fire to the Rain' hitmaker has marked the 10th anniversary of her seminal second studio album, and confessed that her memory of making the record and how she felt at the time is blurry.

She captioned the artwork on Instagram: "Well I never! Happy 10 years old friend! 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 (sic)"

The 2011 LP - which featured hit singles such as 'Rolling in the Deep' and 'Someone Like You' - was written after the 32-year-old singer's separation from her then-partner.

Adele is rumoured to be releasing her hotly-anticipated follow-up to 2015's '25' next month.

And the ’Skyfall’ hitmaker has once again poured her "heart and soul" into the new record and found music "like therapy" after the end of her marriage to Simon Konecki in 2019.

A source said previously: "Adele is pouring her heart and soul into this record, including how she feels post-divorce

"She's been a fan of Raphael since she was a teenager and loves his back catalogue. She wants her next album to be full of soul, with a more eclectic sound.”

The Grammy-winner's close pal, Alan Carr, recently teased that the album sounds "so amazing".

The 44-year-old comedian - who got Adele to officiate his Los Angeles wedding to Paul Drayton in 2018 - spilled: "I’ve heard some tracks on it.

“Oh my gosh, it’s so amazing. It’s so amazing.

“I said to her, I said, ‘That voice is like an old friend.’ It’s like an old friend. Because there are some people [on] the charts who sound a bit like Adele and you go, ‘Oh they sound [like] Adele,’ and then when you hear Adele’s voice again you go, ‘Oh no, there’s only one. There’s only one Adele.'”