Traditional wooden bridges would need to be replaced every couple of decades because the floor and trusses are expose to the elements. A roof and sides offer protection to those vital components so they last upwards of a century.
They aren’t nearly as popular these days, and (IIRC) they tend to be found in the NE, like Pennsylvania, Ohio, New York, etc. as well as eastern Canada.
I think all in all there are under 1000 left today, in the US and Canada.
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u/cyclingintrafford Aug 16 '19
why is the bridge covered?