Before starring in MTV's The Hills, the cameras followed Lo and Lauren while at high school for the show's predecessor, Laguna Beach: The Real OC.
Reflecting on her teenage years last night, Lo posted the picture on Twitter that was taken at the girls' graduation ball. Look how young they are!
Lauren and Lo's graduation dance featured in Laguna Beach the TV show and saw the BFFs getting emotional as they prepared to leave school.
Many of their Laguna co-stars are in the snap, including Lauren's on/off boyfriend at the time Stephen Coletti and his other on/off squeeze at the time Kristin Cavallari!
Alongside the photo, Lo joked: "#tbt SENIOR PROM 2004 - The Wild Bunch."
Well, it's far to say many of the gang's lives have changed in the last 10 years. Last month, Lauren - who is now a fashion designer - married her lawyer husband William Tell in California.
Lo, who now lives in New York and attends culinary school, flew back for the Californian nuptials and was her bridesmaid. Aww!
Meanwhile, Kristin has also gone on to forge a successful career. Along with being mum to two sons, Kristin has her own shoe line and co-hosts E!'s Fabulist.
To see where all the Laguna Beach gang are now, check out our gallery!