Until recently, Cambodia was happy to let the temples of Angkor exist as a beacon of Khmer pride, rising from a jungle canopy like jewels dotting a green silk scarf.
Then the ancient Buddhist and Hindu monuments became the pillars of Cambodia's nascent tourism industry, and officials now count on them to lift the country out of a downward economic spiral.
But others worry the very survival of the 9th- to 14th-century temples may be in jeopardy as planeloads of tourists traipse through hallowed corridors, climb stone steps to shrines, and brush fingers on the bas reliefs of gods, goddesses and demons.
The concerns are typical of the debate about ancient monuments around the world, from the Pyramids of Egypt to the Taj Mahal in India: How do you balance the hunger for tourism dollars with the need to protect legacies for future generations?
Cambodia's government has vowed it will do everything to protect the 40 or so sacred Angkor structures on the outskirts of Siem Reap, a town in the north.
Conservationists and critics of tourism development are not convinced.
"The temples are under severe pressure," said Tamara Teneishvili, who works for UNESCO on conserving the complex, including the world's largest religious monument built of stone -- the Angkor Wat, Cambodia's national symbol.
"The serenity of one's visit to Siem Reap and the temples [are] what's magical and, unfortunately, that's in jeopardy," she said. "... Instead, people are trying to turn it more and more like Las Vegas."
Prominent Cambodian architect Vann Molyvann agrees. He led the government agency in charge of Angkor's development for seven years, but was fired in 2000 after refusing to back down in a dispute with developers over building codes for Siem Reap.
"It could be catastrophic. Siem Reap-Angkor cannot cope with the impact of mass tourism," he said. "It will be a disaster for us if as many people come as they say will."
Some 250,000 foreign tourists visited the temples in 2001, up from 60,000 in 1999, according to government figures. The government's goal is 1 million visitors annually by 2010. Tens of thousands of Cambodians also come each year.
The Apsara Authority, in charge of Angkor's development, acknowledges that the influx is a concern but maintains that it has time to improve the small town's outdated infrastructure. Still, donor and private funding for improvements in water, sewage and electrical systems haven't been arranged.
The government has rejected requests from businesses to start a sound and light show for Angkor Wat and a plan to build an escalator to the top of a hill that provides stunning views. But it granted permission for a company to take tourists aloft in an anchored hot-air balloon.
Built by a series of god-kings who ruled an empire that covered much of mainland Southeast Asia for 500 years, the temples were forgotten for centuries and preserved by dense jungle until a French explorer stumbled on them 140 years ago.
Angkor Wat is the best known, but monuments such as Bayon, Angkor Thom, Preah Khan, Banteay Srey, Ta Prohm and Roulos are other favorites.
During much of the modern boom in international travel, tourists stayed away from Cambodia as it suffered through a series of civil wars. After elections in 1998 seemed to solidify peace, visitors began pouring in.
Until five years ago, a visitor could be virtually alone while watching the sunset from Phnom Bakeng, a 230-foot hill between Angkor Wat and Angkor Thom. Today, the peak is elbow-to-elbow with people at dusk, and its base is a jam of honking tour buses, cars and motorbikes jockeying for space.
"It's a view pollution," UNESCO's Teneishvili said.
Vann Molyvann fears that the temples will crumble unless cars are banned from the temple park -- a large swath of jungle and savanna -- and aircraft stop flying directly overhead.
Such drastic measures are required to reduce stress on the buildings, most of which were built without mortar, he says.
"Vibrations are slowly destroying the temples," he said. "The current flight path [to a nearby airport] is directly over the Bayon and a crash could destroy it."
Government officials disagree that development will harm the temples, let alone cause destruction.
Officials with the Apsara Authority say that a ban on vehicles is being studied and that a new international airport for Siem Reap could open in 2012.
There are varying figures for income generated by tourism. But estimates range from $200 million to $450 million in 2001, making it a major engine driving an economy that otherwise depends largely on foreign aid.
"Angkor can help the whole country by bringing people with money to Cambodia," said Chap Nhalyvudh, governor of Siem Reap province.