Valid question I am glad you asked! Under preparedness is common in all outdoor sports. Mitigating the danger and making sure you’re having a good time should be of utmost importance.
Water
This may *seem* obvious, but you need a lot of water in a canyon. While working as a recreation guide, I occasionally explored canyons with groups. Most people would run out of water before finishing. This generally lead to a sad sight of children asking their parents for more water and parents having to tell their kids they are rationing. As guides we started asking people if they had brought water, then how much water did they bring.
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