This 200ft long bridge in Hunan Province,China might give you chills when you walk through it. This is a see-through 'sky walk' built on a Tianmen Mountain. Kilometre and a half up a sheer rock face the walkway allows visitors to look down at the peaks of smaller mountains below.
The 3ft-wide, 2.5in thick glass walkway is so scary that sightseers are requested to wear cloth slip-ons over their shoes when they cross the skywalk, presumably to help cleaners, who would have to dangle dangerously underneath to wash the glass.

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