The site of Sydney's harbourside brutalist building Sirius, which was once home to more than 100 social housing residents, could become anything from a club, a hotel to even a brothel.
Under planning changes proposed by the NSW government, the zoning of the site - which has been used for social housing for more than 30 years - would change in preparation for its sale.
Under the proposal, the Sirius building can be demolished and turned into a boarding house, commercial premises, a club and a sex shop among other options, but it can also remain as it is.
"We are not discouraging an adaptive reuse of the site," Department of Planning and Environment executive director of key sites Anthea Sargeant told AAP on Wednesday.
If the site is demolished, the new development will have a restriction to limit its height to the deck of the harbour bridge.
The restriction was imposed to "open up the views" of the area, Ms Sargeant said.
"If a person was standing on the pedestrian walkway on the bridge, they'd be able to look out over Circular Quay to Sydney Opera House and have an uninterrupted view of the Opera House," she said.
But, a Millers Point resident who asked not to be named, has lived near the Sirius building for 11 years and thinks the block should "completely go".
"It's ugly ... it's an embarrassment to Sydney harbour," she told AAP on Wednesday.
However, community group Save our Sirius has no intention of letting the brutalist block be knocked down because of its cultural and social significance.
The group, which has registered its interest in buying the Sirius site, said if any developer's plans don't align with the values of SOS or the Construction, Forestry, Mining and Energy Union, the green ban on the site will be enacted.
"Then, no unionised labourer will work on the site," SOS chairman Shaun Carter told AAP on Wednesday.
"This is such a culturally significant thing and we have to defend that for Sydneysiders."
If enacted, the Sirius site's colourful history will come full circle as the social housing block was born out of the green ban movement in The Rocks in the 1970s.
A green ban was imposed to stop the state government from demolishing the area's historic buildings with community groups at the time allowing the lift of the ban in return for the construction of a public housing block that became the Sirius building.
The government's proposed planning changes for the Sirius site are on public exhibition until February 16.