The Pyrmont Bridge is a swing bridge over Cockle Bay in Darling Harbour (part of Port Jackson) in Sydney, Australia.
The foundation stone for the bridge was laid on 6 December 1899 by the Hon. E. W. O’Sullivan and the bridge was opened for traffic on 28 June 1902 by the Governor of New South Wales, His Excellency Sir Harry Holdsworth Rawson KGB.
The engineer was Percy Allan (1861–1930). The bridge had one of the largest swing spans in the world and it was one of the first to be powered by electricity.
Engineers Australia has recognized the bridge as a National Engineering Landmark.
The bridge was closed to vehicular traffic in the 1980s, the traffic having been diverted over new freeway structures built further south of Cockle Bay, and it was then re-opened as a pedestrian bridge as part of the re-development of Darling Harbour as a recreational pedestrian precinct. It now also carries an elevated monorail which travels between Darling Harbour and the Sydney central business district. The monorail track rests on a pivot that allows the track to remain stationary while the bridge swings underneath, so monorails can continue to cross even when the bridge is opened.