Peace protesters who have been camping in Parliament Square since May have been evicted.
Last week the Court of Appeal rejected an application by demonstrators at the camp, dubbed Democracy Village, who wanted to be allowed to remain.
Bailiffs and police moved in at about 0100 BST, although a handful of activists tied themselves to scaffolding.
They have now been removed and a fence has been put up around the square.
A group of people have continued their protest on the pavement with some brandishing banners emblazoned with "the dispossessed".
They say they will go back when the fence comes down.
However the eviction order is not to be applied to the best-known protester in Parliament Square, Brian Haw.
Mr Haw, from Redditch, Worcestershire, who has camped there since 2001, successfully fought to be allowed to continue his demonstration after it was made illegal to hold an unauthorised protest within a square mile of Parliament in 2007.
It took about 60 bailiffs four hours to remove all the protesters.
Londoner Maria Gallastegui, 51, said: "No-one was hurt but people were forcibly removed.
"There are certainly a few bruises."
She added that at least one protester was chained to the scaffolding and another was on top of a lorry containing fencing which was to be put around the square.
Anti-war demonstrators and climate change activists had been among those who set up camp in the square, opposite the Houses of Parliament.
London Mayor Boris Johnson, who took legal action to remove the Democracy Village, had criticised the spectacle as "nauseating".
A spokeswoman for the mayor said the protest had caused "considerable damage" to the site.
"The square will now be closed temporarily, during which time the site will be restored for the use of Londoners, visitors to the capital and responsible protesters," she added.
The leader of Westminster Council Colin Barrow said he was "relieved this dreadful blight of Parliament Square has finally come to an end, and look forward to it being restored to its previous condition so all Londoners can visit and enjoy it".
He said it was wrong for the square to be "hijacked by vociferous minorities" who had turned it into "a squalid campsite".
Critics say other groups have been unable to use the square for their protests, and there have also been concerns about public health because of the lack of toilet facilities.
But although solicitors representing the protesters said there would be no appeal against the decision to uphold the eviction order, protest organiser Chris Knight said: "We're not going very far and we're not going away."
Some protesters have promised a wave of further demonstrations, dubbing the campaign "Operation Rolling Thunder".