The distinctive main building of the old Royal Alex in Dyke Road was built in the 1880s and has been a dominant feature of the area ever since.

Despite various internal changes over the years, the original facade has remained intact.

When the NHS moved out in 2006 and developers Taylor Wimpey bought the site, conservation groups knew they would have to fight to save the building.

And for the past three and a half years this is precisely what they have done.

Led by the Montpelier and Clifton Hill Association (MCHA), groups from across the city joined forces to throw their weight behind the campaign to keep the building in place.

And it seems to have worked.

Taylor Wimpey had a planning application to demolish the site and replace it with flats thrown out, and an appeal rejected.

Now Brighton and Hove City Council has published a draft planning brief, which says any future development plans for the site should keep the main building.

It is a time for celebration for campaigners but they know they cannot relax because there are many other buildings around the city to keep an eye on.

Those being kept under close scrutiny include St Peter’s Church, the Old Market in Hove, Stanmer Church and the Barry Building at the Royal Sussex County Hospital in Brighton.

MCHA chairman Roger Amerena said: “These buildings are an important part of the fabric of the city and make a positive contribution.

“It is like a dripping tap.

If we allow even a few buildings to disappear, over a long period of time we are going to end up with nothing.

We need to fight to protect every one if we can.”

The Royal Sussex is coming under particular scrutiny at the moment because hospital bosses have unveiled £400 million plans to pull down its older buildings, some of which are more than 180 years old, and replace them with radically different 21st century designs.

Hospital managers say the buildings, which are not listed, are too old and dilapidated to provide the care people need.

Mr Amerena said: “It is something conservation groups and societies will be keeping a very close eye on.”

A recent success story was Brighton Society’s fight to get the former Connaught School in Hove listed status, giving it much stronger protection against development.

The Victorian school is now classed as a Grade II building, meaning there will be strict controls on any alterations and it cannot be demolished without proof it is absolutely essential.

Although it appears the Royal Alex could be protected, it is tempered by the need to make sure any developments are financially viable as well.

While the main historic building would be kept, the future of others in the site, including the Elizabeth Day Centre, the laundry building and the nurses home are not so secure.

Keeping them would mean few green spaces and a cramped site, making it harder for developers to make the best use of the area.

The briefing has also taken into account the District Valuer’s view that the site is of borderline profitability for the owners because of the property slump – even if all the buildings were demolished.

The city council admits it may have to be flexible when it comes to assessing the proportion of social housing and size of buildings and flats.

Campaigners, conservation groups and the council are now waiting to see what Taylor Wimpey’s next step will be.

A company spokesman said: “While we understand the aspirations of the brief, for the site to come forward for development, any proposals put forward need to be viable to be delivered.”

The planning brief is expected to be approved by city council member for the environment, Geoffrey Theobald, next week.

He has told The Argus: “Ideally we need a policy which reflects the community’s desire to keep the basic character provided by the current buildings.

“At the same time we need to be wary of any policies that might cause buildings to lay empty for years and become an eyesore rather than an asset.”