How was the Sydney Harbour Bridge built?
The Sydney Harbour Bridge was built by constructing two halves of a steel arch outward from each shore, held back by huge steel cables, until they met in the middle in August 1930.
Construction began in 1923 with the building of approaches and the giant granite-faced pylons. The British firm Dorman Long and Co won the contract with a design for a two-hinged arch, overseen by chief engineer John Bradfield.
Steel for the arch was mostly imported from England, then fabricated in workshops at Milsons Point. Creeper cranes crawled along the top of each half-arch, lifting steel pieces into place.
Meeting in the middle
As each half grew, it was anchored by 128 steel cables tied back through horseshoe-shaped tunnels in the rock on each shore. In August 1930 the cables were slowly released and the two halves met.
The road deck was then hung from the arch. Before opening, the bridge was load-tested with 96 steam locomotives placed end to end.
About 1,400 workers built the bridge, and 16 died during construction. The bridge opened on 19 March 1932 and remains one of the world's largest steel arch bridges.
Did You Know?
The bridge's four pylons are mainly decorative; the arch rests on huge bearings at each end.