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The Union Bridge (1875-1907) was the first to link the Point with the opposite shore of either river. It was built so low that it obstructed river traffic . By 1899, it was a major cause of the Secretary of War to require all bridges on Pittsburgh's rivers to be raised higher or replaced. The Union Bridge was the last wooden river crossing to be built in Pittsburgh. It was replaced by the Manchester Bridge.

These designs also show the seven wooden covered bridges which once crossed Pittsburgh's three rivers between 1818 and 1924.
See other designs featuring the eight Pittsburgh bridges representing various structural types and the Manchester Bridge Portal.