One Direction Celebrates 10-Year Anniversary on Social Media

It's been 10 years since One Direction first came together, forever changing the lives of five young men from the UK.

In honor of the anniversary, four out of the five 1D members -- Harry Styles, Niall Horan, Liam Payne and Louis Tomlinson -- took to social media to reflect on their time in the boy band. However, Zayn Malik, who left the group in 2015, has yet to acknowledge the milestone.

One Direction was formed under the guidance of Simon Cowell and the British version of "The X Factor" in the summer of 2010, igniting a pop-culture phenomenon that will undoubtedly go down in history. Although they've been focusing on their solo careers since the band went on an indefinite hiatus in 2016, the group (minus Zayn) made sure to take the time to celebrate the 10-year anniversary.

"I've been struggling to put into words how grateful I am for everything that's happened over the last ten years. I've seen things and places that I'd only ever dreamt of when I was growing up," Styles, 26, wrote alongside a photo of the group on Instagram. "I've had the pleasure of meeting and working with some of the most incredible people, and gained friendships that I know I will treasure for the rest of my life. None of this would be possible without the support you've given along the way. And for that, I will be forever thankful."

"I just can't believe it's been ten years," he continued, before thanking the band's crew and fans. "Thank you to our crew, our team, and everyone else who helped us along the way. To all the fans, I love you, and I thank you with all my heart. You did it all, and you changed everything."

Harry concluded, "And finally.. to the boys, I love you so much, and I couldn't be prouder of everything we achieved together. Here's to ten. H"

Niall, 26, also posted on Instagram, sharing a photo of 1D in concert.

"When I met these four gents there was no way I thought we would go on to do what we did," he captioned the pic. "So many unbelievable memories we shared together. We felt the adoration of millions from around the planet on a daily basis and it was mind blowing. It's such a major part of our lives and always will be. Cheers to US today boys and thank you to all you beautiful people who have supported us over the last 10 years."

Liam, 26, tweeted a photo of a text message he sent his father when the band won "The X Factor."

"What a journey… I had no idea what we were in for when I sent this text to my Dad ten years ago at this exact time the band was formed," he wrote. "Thanks to everyone that's supported us over the years and thanks to the boys for sharing this with me #10YearsOfOneDirection"

A few hours later, the "Strip That Down" singer added, "It's been so great to reconnect with so many amazing people today. I just wanna take a second to thank all the team behind 1D and crew who helped us everyday [sic] we couldn't have done it without you."

He continued in another tweet, "All those tours albums and good times took some serious planning and hard work...whether it was masterminding a route around the world for us to take or putting up the stage everyone did such an amazing job and became friends and people we would never forget... what a team... here's to a whole lot of history #10YearsOfOneDirection."

Similarly, Louis, 28, also posted about the anniversary on Twitter.

"Feeling pretty emotional today. 10 years!!" he began. "Spent the morning watching old interviews and performances. Just wanted to send a massive thank you to ALL of my band mates. What we did together was incredible."

"Too many incredible memories to mention but not a day goes by that I don't think about how amazing it was," he continued, tagging his former bandmates. "@NiallOfficial @Harry_Styles @LiamPayne @zaynmalik So proud of you all individually.

"And to the fans. The people who gave us all these amazing opportunities," Louis added. "You are incredible, your unmatched level of loyality [sic] is something that makes me really really proud. Miss it every day!"

Simon Cowell shared his thoughts on the momentous occasion.

"Today is a very special day. I was lucky enough to meet five guys," he wrote alongside a throwback photo of the group. "Who were so much fun. So talented."

"It feels like 10 minutes ago," he added. "And you made it happen."

Meanwhile, One Direction's social media accounts also posted in honor of the anniversary, including an epic video montage on the boy band's YouTube page.

The 5-minute clip takes a look back on One Direction's epic journey as a band. Watch the heartwarming video, below.

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