Penobscot Narrows Observatory Bridge and Fort Knox State Historic Site Sign, Maine, USA

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Tallest bridge observatory in the world.

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Size: 3264px × 4896px
Location: Prospect, Maine, USA
Photo credit: © Vicki Beaver / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: engineeringengineering, featengineering, man-, marvelmanmade, narrowsbridge, observatorymainehistoric, signhistoric, sitebridge, sitebridgepenobscot, sitehistorical, sitesightseeing, structureengineering, tourism