You'll probably only get this if you're from the UK, but I used to think the Wombles lived at Wembley Stadium.
A childhood belief about sport

others believed things like this
- I used to believe there were loads of Wombles, until about a minute ago...— Nat
- "The wombles of Wimbledon Common are we" meant that there were loads of them...— Mike
- It never occured to me as a child that teachers lived in houses. I thought they lived at school...— Heidi, Pittsburgh, PA
- i used to believe that a ghost lived under my bed and that a giant lived under our dining room table.— nameless
- when i was 4 my mom told me we lived in Indiana and i would tell people we lived in DianaAnon
- When i was small i used to think god lived on top of my house and the devil lived right underneath it.— Missuss D