The doors to the Luna Lovegood open casting didn't open until 9.15am on Saturday morning but people started queuing on Friday night!
It was the first film casting for Louise, 14, from London and so she was a bit nervous - but very excited!
Sophia, 15, from Hendon started queuing at 6.30am in the morning!
An estimated 15,000 people turned up and the queue snaked up and down both sides of streets around Westminster Central Hall.
This wasn't the first casting queue Lottie, 16, from Teddington had been in. She and her mum came prepared with folding chairs so they didn't have to stand up for hours!
Jessica, 14, from Surrey said "I've done other auditions but really wanted to be here as it's something really special!"
Loads of you kept busy by texting your mates...and Newsround!
Rona, 14, from London said her dad persuaded her to go along even though she had never been to an audition before!
The queue started moving slowly once the casting started.