1. Elsa, the queen of Arondale, was originally supposed to be a villain.
2. The names Hans, Kristoff, Anna and Sven are a tribute to The Snow Queen author Hans Christian Andersen.
3. Walt Disney wanted to make a movie based on the short The Snow Queen, which inspired Frozen, since the 1940's.
4. Since the movie frozen was released, Elsa and Anna have become popular baby names for girls.
5. Fifty different animators worked on the scene in which the ice palace is built. The production team visited a hotel made of ice for inspiration.
6. In March of 2014, two Boston firemen sang "Let it Go" to a little girl trapped in an elevator to calm her down.
7. The painting in the palace gallery is a representation of Jean Honore Fragonard's The Swing.
8. Limited edition Frozen Anna and Elsa dolls have been selling for $10,000 on eBay.
9. Olaf references Bert's penguin dance from Mary Poppins when he performs "The Summer Song".
10. Online searches for flights to Norway have increased by 153% and tourism in Norway has drastically increased since Frozen premiered.
11. Frozen is the highest grossing animated film of all time.
12. Because of her braid, Elsa has 420,000 CGI strands of hair, 10 times the amount of Rapunzel.
13. An actual reindeer visited the studio to serve as inspiration for the character of Sven.
14. The longest single frame in the movie took 132 hours to complete.
15. The animation team created a snowflake generator program to build 2,000 different snowflake designs.
Source: "54 Things You Never Knew About Frozen"