I didn't believe this 100% but I thought that when you travel by car the roads moved and the car stayed still. I only ever thought this on long trips (on a highway, when the road doesn't split up as much as in town). The thought never occured to me whenever I was being driven in town.
I was about 3 or 4. Then I realised three things that disproved my theory:
1. It would get confusing when you have to turn off one road and onto another (the road would have to change directions)
2. I was standing outside and saw many cars move along the road
3. How did the road manage to move in two directions at the same time whenever there was oncoming traffic?
As Isaid, I didn't 100% believe this myself, it just made me feel better knowing there was an explanation for how the car moved :)
A childhood belief about cars

others believed things like this
- On family road trips, my parents always told me that water towers were filled with chocolate.— Edith
- I used to believe that "the motorway" was one big long road that went absolutely anywhere in the world!!!Anon
- i always thought that a DEAD END sign
as where they put all the road kill.
— pav - I thought when a road sight said Dead End that someone had actually died there.Anon
- I thought you were supposed to drive down the center of the road.— Cassiopeia
- I used to see "End Road Work" signs, and thought they were a sort of protest.— Sebastian