Here's another take, with more detail from
The Australian.
(Measurements are in meters - if you are not bimetric, just multiply by 3 for close enough).
"
The allure of the park's treacherous features combined with a population of tourists more accustomed to Disneyland than the great outdoors can contribute to a false sense of security.
"A lot of people who visit Yosemite aren't necessarily familiar with nature," said park spokeswoman Kari Cobb."