I used to believe that the "source" of a river, was a bottle of Heinz Tomato Ketchup stood in a cave, in the hills, with the water trickling out from under it.
A childhood belief about water

others believed things like this
- I used to think that a tornado was a tomato and lots of tomato juice would got flying around.— sam
- When I was little, I thought ketchup came from ketchup trees— cristina
- I used to believe that records were the power source for record players.— bob
- "Traffic lights are operated by monkies inside of them" or so a very reliable source informed me.— guuy
- I used to think Tomato soup was Lava.— Daniel Green
- My mum used to tell me that baked beans were just peas covered in tomato sauce.— munky