If you ignore the big sign that says DO NOT SWIM and go in the water anyway, yes, you get into big trouble.

It's no surprise at all that the majority of medical issues and callouts are on the trail between Half Dome and Happy Isles. Half Dome could be (should be) described as an "attractive nuisance." Everyone, whether they have ever hiked a mile before or not, feels that they MUST DO IT AT ALL COSTS and make the attempt - or so you'd think looking at the statistics. Bad shoes, no water, no common sense, no experience, doesn't matter. I've given away more water, snack bars and advice on that trail - so I rarely go up it any more. And only in the wee hours of the morning before the tourist rush.

I met one of the cable rangers on her way down for the day, last year. She told me the permit system had cut the number of daily incidents from a dozen to less than six. That's kind of huge.
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"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

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