Campaigners have vowed to "fight for every scrap of greenbelt left" after plans to build a huge tomb were dropped at the eleventh hour.
The new mausoleum was due to be built next to Westminster Cemetery, in Milespit Hill, Mill Hill, but proposals were withdrawn two days before they were due to be heard at the planning committee.
Barnet Borough Council officers had recommended the application be rejected, citing it would be too "intrusive, inappropriate and unjustified".
More than 1,000 people rallied together to block the plans, but they are now fearful developers Monument Investment Holdings could come back with a second application.
Mill Hill Preservation Society member John Gillett said: "There was fierce opposition for this so we’re happy – but with a certain reservation. We don’t want to go through this again.
"There was so much wrong with this application, but we are now anxiously waiting to see if they come back with something different.
"We do want to encourage investors to bring us good things to Mill Hill and don’t want to be labelled as nimbys – but they should be under no illusion that we will fight for every scrap of green belt we have left here."
It would have been the first multi-faith mausoleum in England – but surveys show there are enough burial plots in the area for the next 60 years.
The application featured a storage room for urns, a new access road and a 43 space car park, but the council’s report said this would destroy trees with preservation orders.
Richard Logue, chairman of the Mill Hill Residents Association, said: "We have won the battle, but have we won the war? I am concerned they could come back with another proposal.
"Rest assured, we will continue to fight this and any other inappropriate developments on the land. It’s wrong to put up huge massive buildings.
"We will work closely with the preservation society on these issues."
Although the land has already been classed for use as a cemetery, it was last used as a pig farm before the Second World War and has never housed any graves.
Others raised concerns the building would "wreak havoc" on the environment, as it is a haven for wildlife, badgers, hedgehogs, slow worms and deer.
Wildlife expert Chris Packham also supported the campaign, saying it would be a "far more fitting memorial" if it could be protected for future generations.
Labour GLA member for Barnet Andrew Dismore led a campaign against the proposals.
He said: "This wonderful result is a real credit to the strong community campaign that has seen off this appalling proposal.
"If everyone sticks together we can fight these unwelcome people off yet again and wear them down instead."
Peter Smallwood, property director at Monument, said: “The planning officer was going to recommend a refusal and we were concerned – we wanted to discuss the comments further with them.
“It also had to do with the fact that the Mill Hill Preservation Society had voiced their opinion. We’re not here to ignore that.
“It’s too early to say if we’ll reapply.”