The Siding Spring Observatory is located on Mount Woorut (at a height of 1165m) approximately 25 kilometres west of the town of Coonabarabran, NSW. Bordering the eastern edge of the Warrumbungle National Park. The ANU land holding covers an area of approximately 151 hectares and includes the Observatory Precinct on the summit of Mt Woorut as well as steep slopes to the north and south.
Siding Spring Observatory was chosen as a dark sky field station for Mount Stromlo Observatory, ACT, after light pollution from the growing city of Canberra began to adversely affect visibility from Mount Stromlo. The Siding Spring site was selected by ANU in 1962 from many other possible locations because of the dark and cloud free skies and the low risk of future light pollution due to the location within a national park. By the mid-1960s ANU had set up three telescopes, together with supporting facilities such as sealed roads, staff accommodation, electricity and water.
The Siding Spring Observatory is the premier facility on the Australian mainland for optical and infrared astrophysics research. ANU has several active telescopes at the observatory including the the 2.3m Advanced Technology Telescope; 24inch Telescope and the 1.3m SkyMapper telescope. The site is also home to a variety of telescopes owned by other organisations including the 3.9m Anglo Australian Telescope; 2m Faulkes Telescope; 1.24m UK Schmidt Telescope; 0.6m Uppsala Schmidt Telescope; 0.5m Automatic Patrol Telescope; 0.45m Rotse telescope; and the Ystar telescope.
In 2012, a bushfire ravaged the site, destroying the accommodation lodge on the site and the visitor's centre and damaging several other facilities.