"the hualapai tribe of arizona commissioned this horseshoe-shaped, glass walkway that opened above the grand canyon in 2007. the skywalk juts off the rim of a side canyon 4,000 feet above the colorado river. despite the vertigo-inducing views, the glass bridge reportedly is very sturdy — it can support more than 71,000 pounds and can withstand gusts of wind over 100 mph."
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