On March 18, 2007, the National Trust Centre at Observatory and Hill and surrounds will be transformed for the first ever National Trust Day – there will be activities, entertainment and refreshments for the whole family. Details to be advised; please check the website, enews and National Trust magazine for updates.
The day will coincide with mass celebrations for the 75th anniversary of the opening of the Sydney Harbour Bridge. The bridge will be closed to vehicles, and it is expected that many thousands of people will walk across it north to south – ending in the National Trust grounds.
The Trust has a long association with the Bridge
The Sydney Harbour Bridge’s southern approach sits directly at the front of the National Trust Centre, Observatory Hill. At the time of the bridge’s construction in the mid 1920s - 1932 the Trust Centre was Fort St School for Girls. Fort St School lost its Prices St entrance, fountain and several buildings to the bridge approach construction.
Students from Fort St School for Girls proudly marched
across the bridge at its opening on March 19, 1932.
Click on image to enlarge
The Sydney Harbour Bridge was entered on the National Trust’s Register in 1974, with the Classification Report prepared by Jim Kerr and Meredith Walker. Reasons for Listing: -
“The bridge is one of the most remarkable feats of bridge construction. At the time of construction and until recently it was the longest single span bridge in the world and is still in a general sense the largest. The bridge has been an important factor in the pattern of growth of Metropolitan Sydney, particularly in residential development in post World War II years. In the 60s and 70s the Central Business District had extended to the northern side of the bridge at North Sydney which has been due in part to the easy access provided by the bridge and also to the increasing traffic problems associated with the Bridge. The bridge, its pylons and its approaches are all important elements in townscape of areas both near and distant from it. The curved northern approach gives a grand sweeping entrance to the bridge with continually changing views of the bridge and harbour.”
The Trust, in recent years, has commented on proposals for adaptations to the bridge. The Trust did not object to these proposals.
Bridge facts
The Sydney Harbour Bridge is a national icon and is internationally recognized as a symbol of modern Australia and its industrial and social maturity. Its design and technical achievement is considered to be of international significance. Although it is third in the world in terms of span it is regarded as the world’s greatest steel arch for its combination of span, width and load bearing capacity and for the difficulties faced in its construction.
In 1815 Francis Greenway had suggested building a bridge from Dawes Pt to Milsons Pt .But it was not until the 1920s that The Sydney Harbour Bridge was under construction with Dr J J C Bradfield as Chief Engineer.
The bridge took eight years to build and was opened on 19 March, 1932. The Chief Engineer also was in charge of the design and supervision of the Sydney City Railway.
The bridge steelwork was manufactured in New South Wales and fabricated in Sydney in shops especially erected on the shores of Lavender Bay. The granite facing the towers and pylons is from Moruya.
The roadway is 150 feet wide and the total length including the approaches is 3,816 feet. The top of the arch is 445 feet above the water level and the roadway is 170 ft above the water level.
Under the heaviest allowable load, the deflection at the centre of the bridge is 4.5 inches, and the maximum thrust at the hinges, (that is, at the ends of the arch) is 19,504 tonnes per hinge.