Harry Potter star Emma Watson has penned an emotional open letter to mark the 20th anniversary of the release of the first film.

Harry Potter and the Philosopher’s Stone, which was based on the book by J.K. Rowling, was released in UK and Irish cinemas on November 16, 2001.

Watson was just 11-year’s-old when she first appeared as Hermione Granger on the big screen.

Now aged 31, the actress has shared some thoughts on that pivotal time in her life, plus, an adorable throwback picture on social media.

Taking to Instagram, she wrote: “Harry Potter was my home, my family, my world and Hermione (still is) my favorite fictional character of all time. I think a journalist once said it was irritating how many times during an interview I mentioned how lucky I was and started counting… BUT I DAMN WELL KNEW!!! And still know.

“I am proud not just of what we as group contributed as actors to the franchise but also as the children that became young adults that walked that path. I look at my fellow cast members now and I am just so proud of who everyone has become as people. I am proud we were kind to each other that we supported one another and that we held up something meaningful.”

“Thank you to the fans who have continued to show their support well after the last chapter closed. The magic of the world wouldn’t exist without you. Thank you for fighting to make it such an inclusive and loving place,” she continued.

“I still miss the crew who made these films all the time. Thank you for all of your hard work too – I know your contributions sometimes get overlooked.”

She signed off saying: “Happy 20th Anniversary Potterheads! We hope you enjoy the Harry Potter 20th Anniversary: Return to Hogwarts which will stream New Year’s day, Jan. 1 on HBO Max. Lots to look forward to.”

Fans will get to hear more of her reflections when she reunites with co-stars Daniel Radcliffe and Rupert Grint for one-off HBO Max special Return to Hogwarts on New Year’s Day.