Australia Square

Australia Square features a perfectly circular tower rising fifty stories above the city. When it opened in nineteen sixty-seven, it held the title of the tallest lightweight concrete building in the world. Harry Seidler, the architect, insisted on this round shape to ensure every office space offered panoramic views of the harbor and to provide the public with a spacious plaza at ground level. During construction, the workers poured the concrete core using a continuous hydraulic lifting process that never stopped for weeks.