The Garden Palace was situated just south of the present Conservatorium of Music and was built for the Sydney International Exhibition which opened on 17 September 1879. The design was cruciform with nave and transepts with a central dome. Under the central dome stood a bronze statue of Queen Victoria. Built of iron, glass and wood with brick foundations, it was said to have cost £192,000  at the time of the opening.
The ground floor covered 5 1/8 acres to which, when the areas of the basement, galleries and tower floors are added, make a total area of 8 1/3 acres.
After the exhibition closed on 20 April 1880 it was used as an auditorium and gallery and to house the first mining and technological museum . It also provided office space for a number of government departments, and the basement was used to house official records (such as the 1881 Census). These were lost when fire broke out at about 5:40am on 22 September 1882 totally consuming the building in about 40 minutes.
Had it survived Sydney would have been very different, and so the Garden Palace may be seen as an aspect of Sydney as it might have been.
 The Illustrated Sydney News, October 1882
 The Garden Palace, entry in the Australian Encyclopaedia (3rd Edition) Vol. 3 pp. 134-5