Sydney Harbour National Park comprises of sections within the Sydney Harbour, its foreshores and several islands. The national park features important Aboriginal sites, military fortifications and historic sites.
One of the most visible pieces of public art in the park is the HMAS Sydney Memorial Masthead. It can be seen on Bradleys Head on the north shore side of Sydney Harbour. All Australian and foreign naval vessels that enter Sydney Harbour are required to give ceremonial honours to the HMAS Sydney Memorial Mast as they pass.