At over 40 metres above sea level, Observatory Hill is the most elevated point in Sydney. It’s at the crest of the rocky ridge that separates Sydney Cove to the east and Darling Harbour to the west. It was known by a range of names over the 19th century, usually reflecting its varied uses based around its elevated siting; these names included Windmill Hill, Fort Philip, Citidel Hill, Signal Hill, Flagstaff Hill and most recently, Observatory Hill.
Observatory Hill was originally covered with vegetation including eucalypts, angophora, blackbutt, banksias, acacias and tea trees. For the local Aboriginal people, it was probably a popular lookout spot because it was the highest point in Sydney.