Marking the 15th anniversary since the premiere of the hit Disney Channel series, the pop sensation, 28, shared a touching tribute to the character which launched her into super stardom.
Cyrus made her name on the hugely popular show that ran for five years, spawning a successful movie.
In the note, dated March 24, Cyrus reflected on the formative period of her life which saw her deal with personal loss, as well as the realisation of her “wildest dreams”.
She began the hand-written message: “Hi, Hannah - It’s been a while. Fifteen years to be exact.
“Since the first time, I slid those blonde bangs over my forehead in the best attempt to conceal my identity. Then slipped a puke-pink terry cloth robe with a bedazzled ‘HM’ over the heart. I didn’t know then... that is where you would live forever.
“Not just in mine, but in millions of people all around the world. Although you are considered to be an ‘alter ego’, in reality, there was a time when you held more of my identity in your glove than i did in my bare hands.”
Cyrus then reflected on how she shared the spotlight with her adolescent alter-ego.
"We had an equal exchange in which you provided a superlative amount of fame in return for the anonymity I could gift to you," she wrote.
"But, a lot has changed since then. You were like a rocket that flew me to the moon + never brought me back down. I couldn’t have imagined when taping myself singing ‘I Love Rock N Roll’ against a white wall in my mum’s friend’s kitchen in Nashville, the name typed in marquee style letters on the front of a first draft script would make my wildest dreams a reality."
The rest of the letter saw her recount deeply personal memories, such as the loss her grandfather – who died during the filming of the first season – and getting her first period.
"I experienced falling in love for the first time in those years," she goes on.
"Embarrassingly started my period in a pair of white capris. Of course on the day a ‘cute guy’ was cast + asked to have lunch with me. Instead I spent it in the bathroom with my Mom sobbing + scrambling to find a pair of fresh denim."
She went on to pay tribute to her co-stars and family, who supported her through the rollercoaster ride her life had become.
"I gained so many friends over the 6 years spent on set. Emily Osment, Mitchel Musso, + Jason Earles became my family. I was seeing them more than my own.
"Well besides my dad who I drove to work with everyday until my Mom let me buy a Prius,” she added.
The pop star then reminisced on the show’s ending, and what it meant for her.
"It was bittersweet to know I would be leaving you (a huge piece of me) behind in Stage 9. Which is where I say I grew up when asked. It was my home,” she wrote.
She continued: "Breathing life into you for those 6 years was an honour. I am indebted not only to you Hannah but to Any + everyone who believed in me from the beginning. You all have my loyalty + deepest appreciation until the end. With all sincerity I say Thank You!"
"To Disney’s entire team, all fellow cast members, special guests, crew, agents + managers, Especially my Mommy who took me to every lesson + audition even when it required leaving town or making a cross country move which my siblings so selflessly underwent."
The note ends: "Not a day goes by I forget where I came from. A building in Burbank, California with a room full of people with the power to fulfill my destiny. And that they did.
"They gave me you. The greatest gift a girl could ask for.
"I love you Hannah Montana. Forever, Miley".
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