We feel old: Britney Spears turns 30!

Dec 2, 2011 at 2:02 p.m. ET

Britney Spears turns 30 today! What is she doing to celebrate the big day?

Britney Spears turns 30

Let's be honest for a second: There was a time when we never thought Britney Spears would live to reach 30. Thankfully, we were wrong — and the Femme Fatale is celebrating the big 3-0 today!

It's been a topsy-turvy road for the pop princess since she really hit the scene in 1999 with "…Baby One More Time." She's endured a public breakup from Justin Timberlake, got married twice, divorced once and had two adorable little boys.

Oh, and there was that head shaving incident in 2007 and the weird relationship with mind-control expert Sam Lufti.

Brit Brit is doing a lot better these days — she's on the last legs of her international tour and is currently in Mexico. How is she celebrating? With a free concert for her Mexican fans.

"I've had so much fun and received so much love from my fans all over the world while performing my Femme Fatale tour which I am grateful for. I want to return some of that love so I've decided to give my fans in Mexico a special night and perform my Femme Fatale show for free," Spears said on her website.

The concert — scheduled for Sunday, Dec. 3 — is being held in conjunction with the Mexican government and will be free to all fans that fit in the venue.

And her celebrity friends back in the states haven't forgot her birthday.

"Happy 30th birthday @britneyspears!!!" fellow Disney alum Christina Aguilera tweeted.

Kim Kardashian even dedicated a blog post to her pal.

"Happy birthday to the beautiful Miss Britney Spears! Welcome to the 30s club, Brit!! I wish you all the best for this next year and beyond. You're going to love your 30s! I love you and hope you have a magical day. Xo" Kardashian wrote.

Sounds like Britney's next ten years are going to be a lot more positive than the last ten.

Image courtesy WENN

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