When I was five or six years old, I believed that 6 meter (20 feet) tall human giants really existed. I was scared that giants could walk upto me anytime and attack me. I probably got the thought from hearing the story of Jack and the Beanstalk where there was a giant that lived in a castle up in the clouds. I now know that giants are just imaginary creatures from Norse mythology that were also known as Jotuns.
A childhood belief about monsters

others believed things like this
- My mom used to believe that the San Francisco Giants baseball team were actual giants.Anon
- i thought that we were all toys in a dolls house and giants playing with us was why we did what we did— Sarah
- that hills were giants buried underground...— tracy g
- I used to believe that everyone on earth was just really dolls for giants to play with.— Chelsea
- When traveling, I used to believe the hills and mountains were graves for giants.— seattle
- I used to believe that invisible giants played with us like I played with my dolls. — Alexandria