Sydney Harbour National Park contains the most diverse collection of fortifications and defence sites in Australia, and most are listed on the NSW State Heritage Register.
The defence history of Middle Head and Georges Head spans the period from 1801 to the Vietnam War. The overlay of fortifications shows the development of coastal fortification and defence technology over 2 centuries.
Historic fortifications along the proposed new walking track have been assessed by engineers to determine the condition and to consider how to repair and make these fortifications safe for visitors. Samples of the concrete were taken from the WW2 structures to inform the specifications for the conservation works. These works form part of the section 60 approval under the NSW Heritage Act for this project.
Repair of the WW2 fortifications is now underway. This includes concrete repairs to the electric light station at the Inner Fort and new structural supports and repairs to the twin 6-pounder gun emplacements and observation towers near Obelisk Beach and Georges Head. Interpretation is also planned so that visitors can find out more about the history of the area and its importance.
Repairs and structural works to the Obelisk gun emplacement, Sydney Harbour National Park. 
Repairs and structural works to the Obelisk gun emplacement, Sydney Harbour National Park. 
Repairs to the Electric Light Station at the Inner Fort, Middle Head, Sydney Harbour National Park.