How Britney Spears Celebrated 16th Anniversary of 'Baby One More Time'

— -- Yep, “Baby One More Time” could legally be driving a car in some states.

The iconic first hit from Britney Spears turned 16 years old this week and to celebrate the milestone, Spears, 32, posted the song art to her Instagram with a special note.

"Happy sweet 16 to 'Baby One More Time'! Where did the time go!?m" she wrote. "Thx to my fans for supporting me since my 1st single #Happy16thBirthdayBOMT."

READ: Britney Spears’ Opening Night in Vegas Draws Rave Reviews

Since that song, Spears has a slew of hits, including " Oops!... I Did It Again," "Womanizer," and "Piece of Me."

She's still making hits and is performing in a two-year residency at Planet Hollywood in Las Vegas.