Railways in Sydney on 9 December 1926 with the first suburban electric service running between Central station and Oatley on the Illawarra line. In the same year, the first underground railway was constructed north from Central station to St James in Sydney's central business district. Electric trains that had previously terminated at Central station continued north, diving underground at the Goulburn Street tunnel portal, stopping at Museum station and then terminating at St James. Other lines were soon electrified. Also, in conjunction with the construction of the Sydney Harbour Bridge which opened in 1932, an additional four-track underground line was constructed from Central
Sydney Harbour Bridge although around 1964, the former tram tunnels and station were converted for use as a carpark for the Menzies Hotel and as public parking. One of the tunnels was converted for use as a storage facility after reportedly being used by the NSW police as a pistol firing range. The Sydney Harbour Bridge requires constant inspections and other maintenance work to keep it safe for the public, and to protect from corrosion. Among the trades employed on the bridge are painters, ironworkers, boilermakers, fitters, electricians, plasterers, carpenters, plumbers, and riggers. The most noticeable maintenance work on the bridge involves painting.