By Jennifer Davis
Updated Nov 23, 2012 @ 9:00 am
Miley Cyrus
Credit: Scott Weiner/Retna Ltd; REUTERS/GUS RUELAS/LANDOV

Miley Cyrus sure has come a long way from her days as tween sensation Hannah Montana, and today she officially exits her teen years as she marks her 20th birthday. She's growing up before our eyes: After she announced her engagement to Hunger Games hunk and long-time boyfriend, Liam Hemsworth earlier this year, Cyrus also debuted an edgy sheered haircut. Girl no more! In celebration of her milestone, take a look back and her see her transformation in the gallery.