Canyons are inherently risky. Flash floods occur without notice on sunny days. Technical skills & surrounding topography knowledge required yet does not eliminate risk.
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Overview: One of the BIG canyons on Zion... This canyon can either be done from the top (full) usually as an overnighter or via the more popular sneak routes as a long day trip. Expect 30+ rappels up to 175ft doing the full or 140ft if doing the sneak route, loads of tricky down climbing, and some nasty keeper potholes when the water levels are low...
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WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.