John Job Crew Bradfield CMG (26 December 1867 – 23 September 1943) was an Australian engineer best known as the chief proponent of the Sydney Harbour Bridge, of which he oversaw both the design and construction.

The Harbour Bridge formed only one component of the City Circle, Bradfield's grand scheme for the railways of central Sydney, a modified version of which was completed after his death.

He enrolled at St Andrew's College and graduated as a Bachelor of Engineering (BEng) in 1889, winning the University Medal.

[4] After graduating, Bradfield began working for the Queensland Railways Department as a draftsman under the chief engineer.

In the same year, he was retrenched due to an economic depression, and instead moved to New South Wales where he became a draftsman in the Department of Public Works.

[4] In 1913 he was appointed chief engineer for metropolitan railway construction,[4] when he commenced his long association with Confidential Secretary, Kathleen M.

The bridge was designed to carry four lanes of road traffic, flanked on each side by two railway tracks and a footpath.

Both sets of rail tracks were linked into the underground Wynyard railway station on the southern end of the bridge by symmetrical ramps and tunnels.

The eastern-side railway tracks were intended for use by a planned rail link to the Northern Beaches,[citation needed] though they were used for tram services from the North Shore to Wynyard station.

The Depression, and later World War II, along with the post-War growth of motor vehicle usage led to projected patronage of passenger services in Bradfield's plan being overestimated.

[9] The City Circle was constructed originally as a stub line to St James, via the Town Hall, Wynyard and towards the Harbour Bridge.

[19] They had one daughter Mary Margaret (1892–1984) and five sons: Edward (born 1893), Anthony Bailey (1895–1974), Alan (1903), Stanley George (1906–1951), and Keith Noel Everal (1910–2006).

[27][29] In 1934 he was awarded the Telford Medal by the Publications Committee of the Institution of Civil Engineers of London for his paper The Sydney Harbour Bridge, and its Approaches.

[30] In July 1936 the Institution of Civil Engineers in London elected Bradfield as a member of council representing Australia.

[31] In August 1940, a plaque was placed on the Story Bridge recognising the contributions of many of those involved, including Bradfield in Brisbane.