This ponderous pile was designed in a grandiose Edwardian style heralding the subsequent pomp of the Georgian era. The Duke of Connaught and Strathern, laid the corner stone on 29 November 1910, and the building was officially opened on 7 April 1915, by Governor-General Lord Buxton. It took over an area previously used by the citizens of Johannesburg as their Market Square, and the residual space in front of the building became the stage for numerous gatherings of a civic and political nature. It was declared a National Monument under old NMC legislation on12 October 1979.