Plans to demolish a treasured Victorian mansion should not be pushed through solely to cater to “a super-rich plutocrat”, campaigners have warned.

Ham & High: The Athlone House Working Group's barrister David Altaras. Picture: Polly HancockThe Athlone House Working Group's barrister David Altaras. Picture: Polly Hancock (Image: Archant)

The mysterious owners of Athlone House, on the edge of Hampstead Heath, are appealing the council’s refusal to grant planning permission to knock down the former hospital building and replace it with an ostentatious eight-bedroom classical-style mansion.

In a rousing speech on the last day of a three-week planning inquiry on Friday, the campaigners’ barrister David Altaras said that the mysterious owners “must compromise” on their luxurious requirements for the house.

He told the inquiry: “The object of the planning system is not solely to cater for the arcane tastes of this ultra-high net worth family, whoever they might be.

He said: “The appellant constantly reiterates that whatever house emerges from the process must be acceptable to a super-rich plutocrat, with extreme requirements for mega-entertainment.”

The proposed eight-bedroom house would contain a basement car park, underground swimming pool and ballroom.

Developer Athlone House Limited is appealing to the Planning Inspectorate to approve the plans following Camden Council’s refusal of the proposals last summer.

More than 5,500 people have objected to the demolition of the former RAF intelligence base, including Monty Python legend Terry Gilliam.

And dozens of them have made their feelings known throughout the 12-day inquiry at the Wesley Hotel in Euston.

Mr Altaras pleaded with inspector Colin Ball to take the views of campaigners just as seriously as those of the expert witnesses.

He told the inquiry: “Too often in the planning process, the views of local residents are, if not ignored, at least substantially devalued by categorising them under a general heading of nimbyism.”

He added: “But if ‘localism’ means anything, it means that local people do have a legitimate interest in development proposals in their locality.”

Campaigners would ideally like to see Athlone House restored to its former glory.

But Athlone House Limited argue that the necessary repairs are too extensive and too costly to carry out.

Barrister Robin Purchas QC, on behalf of Athlone House Limited, told the inquiry: “It is not at clear whether there is unanimity as to what form that should take, and in particular whether it should simply be the preservation of the dilapidated remnant of the former house as exists on site today as some form of public memorial to past times of opulence or... some form of proper restoration back to its ‘glory days’.”

The inquiry also heard from barrister Morag Ellis QC on behalf of Camden Council, who urged Mr Ball to dismiss the appeal.

A decision is due in six to eight weeks.