"Thank you for keeping this alive for so many years," Lucy Hale looks back at 15 years of Pretty Little Liars

As the popular series 'Pretty Little Liars' turned 15 recently, Lucy Hale, who played Aria Montgomery took a trip down memory lane. The actress, on Monday, took to her Instagram account to share behind-the-scenes moments from the hit series that aired from 2010 to 2017.In the heartfelt post, the 36-year-old gave fans a peek into life on set with a series of throwback photos and videos. Calling the milestone "15 years of PLL--the nostalgia!!", Hale reflected on how much the show meant to her and how it shaped her life."Some of these photos are so low quality, but it really was a different time, lol. The last slide is a video I stumbled upon and didn't even realize I had. Just a small, but not uncommon moment while filming this show.This experience changed my life, and I will always be grateful to everyone involved. And to all of you, who made this one incredible ride. Thank you for keeping this alive for so many years, and I know it'll be one that people will keep discovering.I want to hear all the crazy A theories you had in the comments," she wrote in her Instagram post.Take a look

According to People, Pretty Little Liars followed the lives of a group of teen girls in Rosewood, Pennsylvania, as they dealt with the mystery of their friend's disappearance--and faced creepy messages from the anonymous figure known as "A." The show was known for its twists, secrets, and devoted fanbase.