In 1873 the Colonial Government of New South Wales purchased the Callan Park site, then known as "Callan Estates", with the purpose of building a large lunatic asylum to ease the severe overcrowding at the Gladesville Hospital for the Insane, at Bedlam Point, near Tarban Creek in Gladesville. The new lunatic asylum was designed according to the views of Dr Thomas Kirkbride, an American. Colonial Architect James Barnet worked with the Inspector of the Insane Dr Frederick Norton Manning to produce a group of twenty neo-classical buildings. These were completed in 1885 and named the Kirkbride Block.