The world's tallest railroad structure when it was built in 1882, this 301ft-high bridge was rebuilt in steel in 1900 – but then partially collapsed in 2003, when it was hit by an F1-grade tornado. The remaining piece, jutting out into the air, is now an observation deck, with an impressive and perhaps unnerving view over the ruined steel piers and the valley below.
Kinzua Bridge Skywalk
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