"The use of Babylon as a military base was a grave encroachment on this internationally known archaeological site," said a report which the U.N. cultural agency presented Thursday in Paris.
UNESCO officials stressed that the damage didn't begin with the U.S. military's arrival nor fully end after it left. Archaeologists took away some of Babylon's finest treasures in the 19th century, Saddam Hussein embellished the site with his own structures, and looters returned when the Americans handed the site back to the Iraqis 21 months after the March 2003 invasion.
Now Babylon is the object of a turf war between newly-empowered Iraqi officials. At the national level, Iraq's state antiquities office, focused on conservation, is up against officials of the province surrounding Babylon who want to attract tourists. They have already provoked concern by leveling a section of the site to create a picnic area.
UNESCO aims to make the 4,000-year-old city fit for the coveted title of World Heritage site, and will work to enforce international conventions on the protection of historic sites "so that what happened to Babylon can't ever happen again," said Francoise Riviere, the agency's undersecretary general for culture.
Archaeologist John Curtis of the British Museum, who inspected the site just after it was returned to Iraqi control, said it was too soon to assess the cost of restoring and fully protecting the site.
Several initiatives to save Babylon have been announced in recent years, but have made little headway. Now, with the decline of violence in Iraq, hopes are pinned on a two-year, $700,000 project financed by the U.S. State Department to develop a program aimed at balancing tourism and archaeology at Babylon.
The Future of Babylon Project is a partnership of the World Monuments Fund, a New York-based nonprofit organization, and Iraq's State Board of Antiquities and Heritage.
A WMF team of experts toured the site last month and came away surprised at the extent of conservation problems to be tackled - some of them cases of good intentions gone bad, such as preserving walls with thick plaster.
"On some walls, the plaster was too thick and fell off, pulling down part of the wall with it," Gina Haney, a WMF expert on the tour, said in Baghdad.
Much of the damage to the site, 60 miles south of Baghdad, is man-made.
European archaeologists carted away the Ishtar Gate, the city's symbol, now in Berlin's Pergamon museum. The Louvre in Paris got the giant stone slab on which King Hammurabi's 4,000-year-old code of law was written.
Saddam turned the ruins into a theme park, paving walkways, building restaurants and a palace on an artificial hill, and even inscribing his name on some buildings.
Jeffrey Allen, an expert with the WMF team, said the 2003 war bought the restoration project some time because it prevented premature, ill-supervised development of the site. But looters rampaged through Babylon after the invasion.
The U.S. military did not immediately respond to requests for comment, but in the past it has said looting would have been worse had its troops not been there.
U.S. forces staffed the site until September 2003, when they were replaced by Polish troops.
The UNESCO report did not single out any nationalities of forces on the base, except to mention "contractors employed by them, mainly KBR," an American company that was then a Halliburton subsidiary.
The report said troops and KBR contractors "caused major damage to the city by digging, cutting, scraping, and leveling."
KBR spokeswoman Heather Browne said the company would not comment before seeing the report, but added: "Our commitment to provide the military with high-quality service, and conduct our operations in Iraq in that regard, remains."
The report said steel stakes were driven into ancient walls, which included fragments with inscriptions from the time of King Nebuchadnezzar II, who ruled 2½ millennia ago and is credited with building the Hanging Gardens of Babylon - one of the Seven Wonders of the World.
A helicopter pad, roads and parking lots were built, and heavy vehicles devastated ancient brick roads, the report said.
The symbolic dragon-snakes adorning many of the structures have been partly smashed.
Today there's no trace of the legendary Hanging Gardens. But no large-scale exploration has been done at Babylon in nearly a century, and according to the UNESCO report, archaeologists believe "much remains buried beneath the earth and there is still a great deal to discover."
By Associated Press Writer Kim Gamel; AP Writer Alfred de Montesquiou in Paris and AP Business Writer John Porretto in Houston contributed to this report