It's been just over two decades since readers first entered the wizarding world in J.K. Rowling's debut novel, "Harry Potter and the Philosopher's Stone," which celebrated the 20th anniversary of its original UK publication on June 26 of last year. Next up is the book's 20th anniversary of stateside release: It first crossed the pond as the rebranded "Harry Potter and the Sorcerer's Stone" on September 1, 1998.

Twenty years is a significant chunk of time, and that achievement hasn't gone unnoticed by "Potter" fans, who tweeted up a storm during last year's milestone celebration. They were at it again on this year's 21st anniversary, leading one fan to quip that it made him "feel super old."

Like many of us who grew up with the books, that's a sentiment with which Rowling agrees.

The outspoken author (and newly-minted Academy member) frequently reflects on her landmark series on Twitter, and did so during last year's publication anniversary, too, saying in a tweet that the decades that have unfolded since the book first hit shelves have "been wonderful." We couldn't agree more.

Rowling may feel old, but as one fan put it on Twitter, she should feel mighty proud, too.