19th century

Sydney played host to Australia's first tallest building in 1824 with the construction of St James' Church. Standing at a height of 52 metres (171 feet), it was commissioned by Governor Lachlan Macquarie in 1819, designed by Francis Greenway and constructed between 1820 and 1824 using convict labour.^[7] The partially complete Sydney Town Hall, built in Victorian Second Empire style, surpassed this height in 1878 with the completion of its clock tower that stood at a height of 57 metres (187 feet).^[8] This title was briefly held until the completion of the Garden Palace in 1879, standing at a height of 64 m (210 ft).^[9] The Garden Palace likewise only held this title as tallest briefly, after its demise from a fire in 1882. Hence, the Sydney Town Hall once again became Sydney's tallest until 1891 with the completion of the General Post Office. Standing at a height of 73 m (240 ft), the GPO was at the time described upon opening by the Postmaster General as a building that "will not be surpassed by any other similar structure in the southern hemisphere".^[10][11]

20th century

Towards the end of the 19th century and throughout the beginning of the 20th century, advances in building technology and design coupled with rising urban land values meant that high rise buildings became an attractive proposition in Sydney.^[12] Considered to be Sydney's first high-rise office building, Culwulla Chambers, was completed in 1912 and stood at a height of 50 metres (160 ft). Designed by Spain, Cosh and Minnett (with Rupert Minnett), the building consisted of 14 floors and cost £100,000 to build, equivalent of approximately $1 million in today's money.^[13] This new wave of construction of taller buildings consequently raised concerns over fire risks, namely the inadequate firefighting resources of the period that failed to reach such heights.^[14] The fire in the 8 storey Anthony Hordern & Sons building in 1901, which resulted in the death of five people, was notably one of the first cases to raise such concerns.^[15] In 1907, Alfred Webb, then the Superintendent of the Sydney Metropolitan Fire Brigade, described how it was "a suicidal policy to allow buildings of 100 feet to go up. Our extension ladders rise to a height of 80 feet, and it might be possible to add another 10 feet to them; but the effectiveness of their working is materially decreased as the height is added to." Additionally, public backlash against increased heights also became apparent during this period, primarily stemming from sentiments that taller buildings did not match the aesthetic of Sydney's streetscape and that they would become a source of increased overcrowding and congestion.^[12] As a result, the Height of Buildings Act was passed in 1912, which limited all new buildings to a height of 46 metres (151 feet). This restriction stunted the height of Sydney's buildings, lasting until 1957.^[16][17]

Despite these height restrictions, 1939 saw the completion of the AWA Tower, which finally surpassed the General Post Office's title as Sydney's tallest after 48 years. At a height of 112 metres (367 feet), the AWA tower also became the city's first building to surpass a height of 100 metres (330 feet), and would go on to stay as the tallest until 1962.^[18]

21st century

A 235-metre (771 ft) height restriction implementation persisted in Sydney's building regulations well into the early 2010s. However, this height restriction was lifted in 2016, allowing buildings to be built as high as 310 metres (1,020 ft) on condition that public spaces were not overshadowed.^[21] This was further raised to 330 metres (1,080 ft) at the end of 2019.^[22]

Sydney's most recent residential tower, 505 George Street, will rise 270 metres, comprising 80 stories much of it serviced apartments. As the tower penetrates Sydney Airport's Obstacle Limitation Surfaces (OLS) it will require an Aeronautical Impact assessment approval.^[23]

The current tallest building in Sydney, and the fourth tallest in Australia is Crown Sydney. Completed in 2020 it stands at a height of 271 m (889 ft), overtaking the Chifley Tower's previous title as tallest in Sydney, standing at a height of 244 metres (801 feet).