It’s 20 yrs since “Harry Potter and the Philosopher’s Stone” arrived in bookstores

It’s been 20 years since “Harry Potter and the Philosopher’s Stone” arrived in U.K. bookstores.

Four years later, Daniel Radcliffe, Emma Watson and the gang would take up the mantle on the big screen. Over the last two decades, the books and films have captivated both young and old.

Here are 10 fun facts you probably never knew about the “boy who lived.”

1 – Why Harry’s eyes weren’t green in the films like in the books.

In the DVD extras for “Harry Potter and the Deathly Hallows – Part 1” in 2011, author J.K. Rowling and Radcliffe discuss why they changed that important part.

Radcliffe, who has blue eyes, had tried on green contact lenses, but he found them uncomfortable, so Rowling said the only important “thing is that his eyes look like his mother’s eyes. So if you’re casting Lily, there needs to be a resemblance.”

“There is a very small percentage of people apparently who have a very extreme reaction to contact lenses. And I was one of them,” Radcliffe added.

2 – Robin Williams rejected?

Yep, the late Oscar winner wanted to play Hagrid in the movies, but apparently there was a Brits-only rule by the producers.

“Robin had called [director Chris Columbus] because he really wanted to be in the movie, but it was a British-only edict, and once he said no to Robin, he wasn’t going to say yes to anybody else, that’s for sure,” casting director Janet Hirshenson told the Huffington Post last year.

3 – What’s up with Hermione Granger’s teeth?

Another change from the book was Hermione’s buck teeth. Christopher Columbus, the director of the first two films, said fake teeth were only used for one scene in the very first film.

“I realized that she’s never going to be able to perform with these huge fake teeth in her mouth for the rest of the movie,” he told EW. So he took them out for the rest of the movie and the rest of the franchise.

4 – Voldemort’s nephew?

Well, kind of. One of the actors who played young Tom Riddle, the orphaned boy who eventually became the dreaded Voldemeort, is actually Hero Fiennes-Tiffin, the nephew of Ralph Fiennes, who played the dark wizard…

MORE: ‘Harry Potter’: 10 things you never knew about the books and films – ABC News