Thousands queued for the opening of the Harry Potter theme park, where they were greeted by the films' stars, including Daniel Radcliffe.
The Wizarding World of Harry Potter opened at the Universal Orlando Resort in Florida on Friday.
Universal Orlando spokesman Tom Schroder said 5,000 people were waiting to get in before the park opened.
Radcliffe said the park, based on JK Rowling's hugely successful novels, was the "next part of the Potter legacy".
Aerial photos showed thousands of people waiting to enter the park for the first time. On Twitter and other forums, they joked that the park had become "Harry Potter and the Endless Line".
The 20-acre site includes rides, shops and reproductions of the fictitious village of Hogsmeade, the Hogwarts School of Witchcraft and Wizardry and the Hogwarts Express train.
"What Universal Orlando has done with Harry Potter is really, really fantastic," said Radcliffe, who plays the schoolboy wizard, at the opening ceremony.
"We're all kind of very grateful that the next part of the Harry Potter legacy has been so well done and so well made."
Radcliffe was joined at the opening by fellow Potter actors Rupert Grint (who plays Ron Weasley), Michael Gambon (Albus Dumbledore), Warwick Davis (Filius Flitwick), Bonnie Wright (Ginny Weasley), Matthew Lewis (Neville Longbottom), Tom Felton (Draco Malfoy) and James and Oliver Phelps (Fred and George Weasley).
The park has two roller coasters and a ride which takes guests on a flight through Harry's life, including encounters with Dementors and a dragon and projections of characters from the film.
Bill Davis, president of Universal Orlando Resort, said: "We have brought to life a cultural phenomenon that has captured the hearts and minds of millions of people around the world."