Lucas Heights is a suburb in southern Sydney, in the disclose of New South Wales, Australia. It is located 31 kilometres south-west of the Sydney central matter district, in the local government Place of the Sutherland Shire. Lucas Heights is located on the Woronora River, which flows north into the Georges River.
Unusually for a suburb, Lucas Heights does not contain a residential area. The residential Place previously part of Lucas Heights was renamed Barden Ridge in 1996 to addition the real estate value of the area, as it would no longer be instantly united with the HIFAR nuclear reactor.