Yep, I learned that again the hard way at Carlsbad caverns a few years ago. By the time I got to the bottom, I could barely stand to walk around the paved path. The cold damp environment didn't help either. It took me a couple days to straighten back out.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)