It is one of Sydney Habour's hidden gems. A sprawling precinct, dotted with empty warehouses and old factories, overlooking the water on Sydney's north shore.
For more than 150 years it has been closed to the public.
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HMAS Platypus site to be redeveloped
Harbour Trust chair Kevin McCann, chief executive Mary Darwell and federal MP Trent Zimmerman have called for expressions of interest at the former HMAS Platypus site in Sydney.
But all that is about to change. The Sydney Harbour Federation Trust is opening up the 1.8 hectare site in the hope it will become Sydney's newest cultural and commercial hub.
Located less than a kilometre from North Sydney's CBD, the site was once a gasworks factory and later became a submarine base known as HMAS Platypus.
![Sub Base Platypus looking towards North Sydney.](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/t/t/8/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)
On Thursday, the precinct was publicly unveiled and relaunched as Sub Base Platypus.
Chief executive of the Harbour Trust, Mary Darwell, said parts of the site will be opened to the public from as early as mid 2018, while restoration work is completed.
"Once completed, we will see Sub Base Platypus become a special destination for Sydneysiders and visitors alike, providing a range of facilities and venues for cultural performances, function areas, cafes and restaurants, as well as offices and commercial spaces," Ms Darwell said.
Chair of the Harbour Trust Kevin McCann, said the "industrial heritage values of the buildings will be retained, [but] the buildings and public spaces will be adapted and made available to cultural, community and commercial organisations."
![The Platypus site was once a gasworks providing gas for street lights, homes and businesses.](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/t/n/0/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)
The former submarine workshops, for example, will be revitalised to provide a sequence of terraces, streets, squares and gardens.
Businesses and community organisations will be able to lease eight buildings across the precinct, including the former submarine workshops, the former torpedo factory, the old submarine school, and the old gas work offices.
![The HMAS Platypus site in North Sydney.](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/s/l/h/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)
The oldest building on the site is the Retort House, a prefabricated iron building which dates back to 1886 and was originally used for the conversion of coal to gas.
As a gasworks, the facility provided provide gas for street lights, homes and businesses on the North Shore.
![The site has been dormant since the submarine base closed in 1998.](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/t/m/r/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)
However, the site was reclaimed for Australia's war effort in 1942 by the Commonwealth Government and it was transformed into a torpedo manufacturing and maintenance factory. It also operated as a service facility for the naval vessels of the Pacific Fleet.
At the height of wartime production, the torpedo factory - the largest building on the precinct - employed 200 civilian workers, a quarter of whom were women. The building continued to be used for torpedo manufacturing and repair until the 1990s
![The site was taken over by the federal government in 1942 and became a torpedo manufacturing and maintenance factory as ...](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/t/k/8/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)
The precinct took on a new role again in 1967, when it became the base of the Royal Australian Navy's Oberon-class submarines and was named HMAS Platypus.
Until now, the site has been dormant since the submarine base closed in 1998.
![The 1.8 hectare Platypus site has been closed to the public for 150 years.](http://web.archive.org./web/20170901015906im_/https://www.fairfaxstatic.com.au/content/dam/images/g/y/7/t/t/9/image.related.articleLeadwide.620x349.gy7omf.png/1504187389721.jpg)