When I was a kid I asked my Dad about the cautionary road sign that said "Watch for Ice on Bridge". Dad told me that every so often the people form the local radio station would place a block of ice on a bridge and if you called in to the radio station and reported it before the ice melted you would win a prize.
A childhood belief about road signs

others believed things like this
- I used to wonder how they managed to fit the orchestra into the radio station.
— sally - I used to think that when a song finished on the radio it would play again on the next station— Maria
- I used to believe that if you spoke into the speakers that they would hear it at the radio station. — natalie
- I use to believe all the people singing on the radio were IN the radio.— Yvonne
- Whenever I was upstairs on a bus, I didn't believe that it would fit under the bridge so I used to duck. — Dave, Lancashire
- I used to believe that George Washington died and turned into a bridge.— lara dean