Pyrmont Bridge is one of the oldest surviving electrically operated swing span bridges in the world. The first bridge began operating in 1857 and the current swing span bridge opened in 1902. Engineer Percy Allan designed the bridge with a young John Bradfield (who later went on to design Sydney Harbour Bridge) designing the sandstone abutment walls at each end. Power to operate the bridge was originally drawn from Ultimo Power House (now the Powerhouse Museum). The bridge provided the main transport route between the city and Sydney's growing western suburbs while the swing span allowed tall vessels to access Darling Harbour.

As the southern end of Darling Harbour became less commercially viable as a trading port, the area gradually fell into decline. When Darling Harbour was redeveloped in 1988, Pyrmont Bridge's swing span was restored.