The proposed Islamic centre, which has caused a storm of debate in New York, cleared its last legal hurdle on August 3. The group behind the Muslim community centre, the Muslim-run real estate company and developer Soho Properties, has bee granted the clearance it needed to build near the site of the former World Trade Center.
The planned building is to be called Cordoba House and will include a prayer room and a 500-seat auditorium as part of a 13-storey Muslim cultural centre.
Those opposing its building have turned to advertising in a last ditch effort to stop the centre being built.
, a group called the American Freedom Defense Initiative (AFDI) is behind the campaign.
The AFDI is run by right-wing blogger Pamela Geller who has previously run campaigns to encourage Muslims to leave their faith.
Geller is reported to have spent almost $10,000 to finance the banner ads, which controversially feature the South Tower of the World Trade Center moments before United Flight 175 struck on 9/11 and a building emblazoned with an Islamic crescent. The ads ask the question: "Why There?"
The ad campaign is running on New York's city bus system, but not before a row over their appearance.
The New York City's Metropolitan Transit Authority (MTA) had asked via its outdoor ad company, CBS Outdoor, for the images of the plane and smoke to be removed. 
Geller, at first, agreed then sued the MTA on free speech grounds. This led MTA to announce earlier this week that it was giving the ads the go ahead to run in their original form - smoking building, plane and all.
The MTA's decision to allow the ads to run has been criticised by New York's public advocate Bill de Blasio who that he could not believe "the MTA would allow it on its buses".
The ad was also denounced by Council on American-Islamic Relations, which called it "anti-Islam extremists".
Jeremy Soffin, the authority's chief spokesman, a spokesman for the MTA, said: "We do the best we can within our guidelines, with the understanding that in a lot of cases, we'll have to put up ads that we may or may not agree with. There will always be cases where people disagree.
"You have people who are purposely trying to be provocative and sometimes, frankly, more interested in the publicity that comes with the conflict, as opposed to the benefit of actually running the ad."
The planned centre still faces possible legal challenges including one from The American Centre for Law and Justice, which represents fire fighters killed in the 9/11 terror attacks.