1. Soos is based on a college friend of series creator, Alex Hirsch.

2. Dipper and Mabel are loosely based on Alex and his twin sister, Ariel.

3. Mabel's fantastic sweaters are also rooted in real life, based on tacky, childhood knitwear.

4. Grunkle Stan is based on Alex Hirsch's grandpa — gold chain and all.

5. According to Hirsch, there was a kid in his high school who had terrible acne and Hirsch would map out his face like the constellations. One day, that kid had a perfect 'Big Dipper' on his forehead, much like Dipper's birthmark.

6. Gravity Falls was inspired by Boring, Oregon.

7. Jason Ritter (Dipper) almost got replaced. He was working on another show at the same time that wouldn't allow him to work on Gravity Falls, so he had to step down from the role of Dipper. However, the other show got cancelled and Ritter came back to Disney as they hadn't found a replacement for him yet.

8. Kristen Schaal was the first choice for Mabel. Hirsch would have stopped working and quit if they hadn't gotten her for the role.

9. Between seasons 1 and 2, the creative team took a road trip up the Oregon coast. They stopped at every tacky tourist attraction and they were surprised how well they had nailed some of the aspects of the Mystery Shack-like shops.

10. There's an animated version of Hirsch in every episode. At the end of the theme song, one of the Polaroid pictures depicts a red goatee that represents Alex Hirsch.

11. There are many hidden 'H's in the show. They're subtle nods to "Hirsch".

12. The most watched episode was "The Deep End", the episode with Mermando.

13. T.J Miller, the same person who voices Fred in Big Hero 6, voices Robbie in Gravity Falls.