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Chowder Bay
Between June 2021 and November 2023, the Harbour Trust – with the aid of specialist volunteers, including ex-servicepeople – undertook work to faithfully restore the Close Defence Battery Observation Post and its sister facility, simply named the Battery Observation Post. These remnant observation posts were part of North Fort, the former Defence complex and artillery battery established at North Head in 1938.
Defence of Sydney
During the Second World War, North Fort formed part of Fortress Sydney – a network of batteries spanning 300km of coastline. Until 1952, North Fort featured a pair of 9.2-inch Mark X breech loading guns, each capable of firing a distance of 26.4km.
Critically, the gunners who operated these two heavy weapons were guided by observation posts along the coast. Each of the Fortress Sydney batteries featured one or more posts. These posts were garrisoned by personnel monitored for enemy forces and communicated intel – including vessel range, course and speed – by telephone to batteries along the coast.
Observe and report
Both of the observation posts at North Head Sanctuary are a concrete blockhouse with a large window, the original purpose of which was to provide those operating the rangefinding and observing instruments with an unobstructed 200 degree field of view.
While both observation posts broadly served the same function, each offered North Fort a distinct advantage. The larger of the two facilities – the Battery Observation Post – was used during the day when it was possible to observe the approach of vessels beyond gun range.
Meanwhile, the Close Defence Battery Observation Post was better suited to observing the approach of vessels at night or during poor visibility conditions, with the aid of searchlights. In addition to being the smaller of the 2 posts, it was also closer to North Fort’s guns.
Communications from the 2 observation posts were relayed to the servicepeople who ran North Fort’s Plotting Room, an underground bunker concealed in bushland. The Plotting Room personnel were then responsible for transmitting firing data coordinates to the fort’s gunners. Notably, members of the Australian Women’s Army Service were amongst the servicepeople who served in North Fort’s Plotting Room and its observation posts.
Heritage amplified
In the decades since North Fort was decommissioned, its remnant observation posts fell into disrepair. This was compounded by the damage they sustained during a 2020 bush fire. In mid-2021, the Harbour Trust commenced efforts to restore both posts, to the extent possible, to their condition during the Second World War.
Following the removal of concrete cancer from both posts, 10 specialist volunteers from the Harbour Trust’s North Head Restoration Workshop undertook a series of projects to turn back the clock on the historic facilities and amplify their heritage values.
These projects included replacing and restoring their blast doors, fabricating and installing new windows, the application of a camouflage paint scheme, the fabrication of replica equipment (including rangefinding instruments), repairing furniture and installing public pathways to improve access to both observation posts.
Additionally, volunteers installed a gate in the sandstone wall adjacent to the Battery Observation Post and worked with nursery volunteers from the North Head Sanctuary Foundation to plant native vegetation the vicinity of both posts.
The Harbour Trust looks forward to providing the public with opportunities to discover North Fort’s observation posts and learn more about the crucial role the facilities once played in the defence of Sydney. It also thanks its restoration volunteers, many of whom previously assisted with the restoration of North Fort’s Plotting Room.
