NEW YORK (AP) -- The furor over how close is too close to ground zero for a planned Islamic center and mosque has raised a simple question nine years after Sept. 11: Where exactly is ground zero? The lines marking the site of the 2001 terror attacks change depending on which New Yorker, 9/11 family member and American you talk to. Even those who know it best can't agree on its boundaries. Tourists who come to snap pictures outside of a busy construction site often aren't sure that they're there. Andrew Slawsky, a 22-year-old college student standing outside the proposed mosque and Islamic center, north of the World Trade Center site, says ground zero is not here. "This is not sacred ground," Slawsky said. "To me, ground zero is any site that was destroyed or damaged on 9/11 - mostly the hole in the ground." But Maureen Santora, whose firefighter son was killed at the trade center, says ground zero extends far beyond the fenced-off construction site where cranes, skyscrapers and a Sept. 11 memorial are rising. It goes through a wide swath of lower Manhattan, where debris was littered on rooftops and body parts were found years later, she says. "It will always be a place where my son was murdered. I don't care what they call this place," Santora said. "It will be a cemetery." The evolving boundaries of ground zero have informed - or misinformed - the debate about its proximity to the planned Park51 community center. The farther away from the place, the bigger it seems. "It's constructed as hallowed ground when people don't actually have a clear boundary for it or a clear sense of what's within the boundary," said Kathleen Hall Jamieson, a University of Pennsylvania communications professor who studies political rhetoric. "What you have is a classic instance of people responding to a symbol whose meaning is physically divorced from the actual space." Ground zero for decades had conjured up images of the atomic bomb blasts in 1945. After Sept. 11, it became a journalistic shorthand that evoked war and devastation, with an Associated Press report on the day of the attacks referring to the ruins of the towers as ground zero. It became synonymous with the World Trade Center site as the debris field left by the attacks - body parts and airplane debris on rooftops and office papers that flew to Brooklyn and New Jersey - got smaller. Since the first months after the attacks, the 16-acre site has been fenced-off and mostly covered. It once housed the ruins of the two towers hit by hijacked jetliners, as well as four other buildings in the complex, including U.S. Customs headquarters and a Marriott hotel. Today, cranes rise high in the air along with an office tower over 30 stories high, a Sept. 11 memorial and a transit hub under construction . Even the public and private agencies closest to the site don't have one definition of ground zero's boundaries. The Port Authority of New York and New Jersey - which owns the trade center site and is rebuilding most of it - says it is bounded by the fence, which has moved a few feet in both directions as construction has progressed. "The fence is certainly the way we think of it," said Steve Sigmund, Port Authority's chief spokesman. The city uses the same boundaries, a spokesman said. The Lower Manhattan Development Corp., a rebuilding agency that decided what would be built on the site, also counts parts of a block south of the fenced-off area as part of ground zero. That includes a former bank tower being dismantled, where officials hope to build another skyscraper. Joe Daniels, president of the foundation in charge of the 9/11 memorial, said ground zero is the fenced-off area, the former bank tower south of the site and 7 World Trade Center - part of the trade center complex that collapsed on Sept. 11. 7 World Trade Center was rebuilt four years ago. It is diagonal from the building where the $100 million Islamic community center is planned. The Park51 project is two blocks north of the fence, in a neighborhood bustling with TriBeca restaurants and hotels and Battery Park City apartment buildings. The World Financial Center, a Burger King, discount clothing outlet, firehouse and Catholic church are among the businesses dotting the site's borders. Rita Balmin, who works in an office building between the fence and the site of the planned mosque, said it's all ground zero, "because all these people who lived in this neighborhood were hurt by the attack." The proposed Islamic center and mosque has caused an intense uproar over the symbolism of Sept. 11 and religious freedom. Hundreds have rallied near ground zero, raising signs that read "A Mosque at Ground Zero spits on the graves of 9/11 victims" and the like. The changing geography is purely symbolic, said Nelson Warfield, a national Republican strategist who has worked extensively in New York. "It's a mixture of geography and conceptual issues," he said. "The concept of an Islamic community center in close proximity to the scene of the greatest attack by Muslim extremists on this country is hard to delineate in terms of lines on a map."