There are a total of 7 Disneyland poster hidden throughout Monsters, Inc. (2001) in the background.
1. When Boo is hitting Randall on the head with a bat, you can see a vintage Disneyland Frontierland poster hanging on the wall above the dresser. It has the Stage Coach Ride, Mine Train Ride, and Mule Pack Ride on it.
2. When Boo starts beating Randall and when Sulley grabs Randall by the neck after Boo beats him, you can see a vintage Disneyland poster on the wall above the bed for the Flying Saucers in Tomorrowland.
3. To the right of the Flying Saucers poster is the vintage poster for the Tomorrowland Submarine Voyage.
4. When Mike is telling jokes in the kid’s room at the end, you can see a vintage Astro Jets Tomorrowland poster above his bed.
5. In the same scene when Mike is leaving the kid's room you can see a Sailing Ship Columbia vintage poster on the wall.
6. When Mike and Sulley are walking to work, they pass Hidden City Café. In the window next to it is Monstro the Whale on the Storybook Land Canal Boats poster from Disneyland.
7. When Tony tosses Mike and Sulley the complimentary fruit, they catch the fruit while standing in front of the Fine Art shop. If you look in the window behind them, you can see a poster for the 20,000 Leagues Under the Sea attraction from Disneyland’s Tomorrowland.
BONUS FUN FACT: Hidden City Café was to pay homage to the now-closed café in Richmond, CA. This was the café used for “The Lunch” meeting with the creative team when they came up with the movies A Bug’s Life, Monsters, Inc., Toy Story 2, Finding Nemo, and WALL•E.