North Dakota, US
The Westgaard Bridge, also known as Souris River Bridge, near Voltaire, North Dakota is a Pratt pony truss through structure that was built in 1902 to cross the Souris River. It was listed on the National Register of Historic Places in 1997. It is the oldest documented bridge in McHenry County.
Listen to the audio guide for Westgaard Bridge Free on WIP — starts by itself when you arrive, even with the screen off