In certain waterparks, they'll be a "lazy river", which is basically a slow-flowing "river" which flows around or through the park. It's about four feet deep and very popular with the elderly, and parents with young children. Well, when I was about four years old, my cousin (five at the time) told me that the grates at the bottom held sharks that fed on toes. Ever since then, i've always lifted my feet above the grates.
A childhood belief about excursions

others believed things like this
- I used to believe that people were buried in "grates".— Grate Job
- I used to think that the river police were there to stop naughty people from pulling the plug out.— Linda
- My Grandmother once told me she could unscrew her feet. I believed that for years.— Andy Bettison
- When I got my feet measured by the electronic machine, I thought that the machine will squash my feet!— Helen
- when i was young i used to believe that chewing gum was made out of cows feetAnon
- i used to believe there were invisible sharks in the deep end of the pool, thanks to my older brother.— Melissa