The Macquarie Lighthouse, also known as South Head Upper Light, is the first, and is the longest serving, lighthouse site in Australia. It is located on Dunbar Head, on Old South Head Road, Vaucluse in the Municipality of Woollahra local government area of New South Wales, Australia. The lighthouse is situated approximately 2 kilometres (1 mi) south of South Head near the entrance to Sydney Harbour. There has been a navigational aid in this vicinity since 1791 and a lighthouse near the present site since 1818. The current heritage-listed lighthouse was completed in 1883. The lighthouse and associated buildings were designed by James Barnet and built from 1881 to 1883.

Old South Head Road is a major road in Sydney, linking the eastern suburb of Bondi Junction to Watsons Bay on the South Head peninsula. It is historically significant because its earliest origins can be traced back to the early days of the colony of New South Wales.