It is described as the best-preserved city in Southeast Asia, a bygone seat of kings tucked into a remote river valley of Laos.
Luang Prabang weaves a never-never land spell on many a visitor with its tapestry of French colonial villas and Buddhist temples draped in a languid atmosphere.
But most of the locals don't live here anymore. They began an exodus from this seeming Shangri-La after their hometown was listed a Unesco World Heritage Site in 1995, and sold itself wholesale to tourism.
It's not an uncommon pattern at some of the 1052 sites worldwide designated as places of "outstanding universal value" by the UN cultural agency.
The international branding sparks mass tourism, residents move out as prices escalate or grab at new business opportunities, hastening the loss of their hometown's authentic character to hyper-commercialisation. But locals may also prosper and some moribund communities are injected with renewed energy.
"If you open the door you will have some fresh wind, but you will also get mosquitoes," says Prince Nithakhong Tiaoksomsanith, a leader in preserving Luang Prabang's artistic heritage.
Since Unesco helped lay down the town's welcome mat, its long-time residents have been replaced by wealthy Lao outsiders, an ever-growing influx of tourists and enough French, Australian, American and other expatriates catering to their needs to have locals rhyme Luang Prabang with "Meuang Falang" - meaning either French or Western town.
Luang Prabang's rich architectural heritage, protected by Unesco's regulations, has been spared the eradication of countless historic sites across Asia. But virtually every home and mum-and-dad store in the historic centre has been converted into a guesthouse, restaurant, cafe, bar or travel agency. The former prison was transformed into a luxury hotel and the French Cultural Centre has become the Hibiscus Massage Parlour.
Scenes of workaday life are rare because as prices shot up — a small plot of land that sold for US$8000 ($11,000) three years ago now goes for US$120,000 — residents moved into surrounding areas, selling or renting their properties to the newcomers.
As former Unesco consultant and long-time resident Francis Engelmann said: "We have saved Luang Prabang's buildings but we have lost its soul."
Similar criticism has been levelled at Unesco's worldwide programme, along with praise for having rescued irreplaceable man-made and natural treasures in 163 countries since its inception in 1972.
Calling it "UNESCOcide", Italian writer on urban development Marco d'Eramo said whenever a city is named a heritage site, it "dies out, becoming the stuff of taxidermy, a mausoleum with dormitory suburbs attached".
Viewing Unesco's programme in a broader context, Dallen Timothy, a cultural tourism expert at Arizona State University, said indigenous heritage worldwide has become the commodity of outsiders "rather than remaining in control of the people whose cultural heritage it really is. It's a matter of powerful versus the powerless."
The director of Unesco's World Heritage Programme, Mechtild Rossler, acknowledged a very fine line existed "between the benefits which need to be shared with the local community and the rights of the visitors". She said Unesco stresses preservation of "intangible culture" rather than just bricks and stones.
Some argue that sites such as the Egyptian pyramids, Grand Canyon and Stonehenge would draw crowds whether they were on Unesco's list or not, that mass tourism is simply a 21st-century phenomenon. But especially in developing countries, the designation can ignite a surge in visitors.
From a trickle, Luang Prabang, a town of about 50,000, attracted more than 530,000 foreign and domestic tourists in 2014 and all projections show steep increases. Rossler said tourists to Japan's Tomioka Silk Mill have soared by 400 per cent since it was named a Unesco site two years ago.
Governments and tourist operators are aware of the benefits a Unesco imprimatur can bring, and use it as a marketing strategy. A tourist sub-group, the WHS baggers, has emerged. Els Slots says her life's goal is to visit every site, having already notched 587.
Laos last month marked the 20th anniversary of Luang Prabang's inscription with a 6000-strong parade accompanied by 20 elephants.
"Emerging countries have bombarded us with new nominations, especially China and India, in addition to European countries, which have always been interested," said Rossler. "Their economic impact is tremendous, even in Europe."
As political pressure is exerted, some sites are approved well before they are properly prepared, Rossler said. The listing is finalised not by Unesco but a World Heritage Committee with members from 21 nations.
In Luang Prabang, the prince said residents, tour operators and Buddhist monks were not ready to cope with the sudden influx. While flyers urging tourists to respect local customs are passed out, some offensive behaviour continues.
One foreigner wanted the prince to arrange sunset cocktails at a hilltop temple and other tourists point their cameras inches from the faces of monks as they pass by on their dawn rounds to collect alms.
Compared with many places, Luang Prabang has generally abided by Unesco's regulations, which include forbidding pane glass and using traditional materials when restoring temples.
Forty eight sites are on a Unesco "danger list" for being seriously degraded by humans or nature — ranging from the birthplace of Jesus in Bethlehem to Florida's Everglades National Park — while two have been delisted for gross violations. Many long-listed sites have yet to present conservation management plans.
"Unesco should be a bit tougher on enforcing the regulations. Some of the sites in danger should be delisted, which would provide an impetus for their host countries to wake up and work on fixing what's wrong," said Arizona State's Timothy.
The agency has few enforcement powers.
Rossler puts failures down to "bad actions of governments" and stresses that Unesco doesn't have the funds or manpower to solve festering problems, never mind the destruction of sites.
In Luang Prabang, reactions of citizens to "moladok" or heritage, are complex. They express pride in being internationally recognised and satisfaction at opportunities for jobs and cash from tourists, hoping even more will come. But they also chafe at the Unesco-imposed restrictions and don't generally share Western nostalgia about a pre-globalisation past, preferring new houses in modern suburbs.
"They say they have lost a sense of belonging to the community, a monastery and its ceremonies, a sense of pride in their old quarter," says Engelmann. "It's not easy to recreate the feeling of belonging to a real community."
Thongkhoun Soutthivilay, co-director of the town's Traditional Arts and Ethnology Centre, said her mother sold her traditional house for a good price and joined the exodus. Life has improved in some ways.
"But we miss our old neighbourhood," she said. "Some things have changed for the good, some for the bad."
Getting there: Singapore Airlines and Silk Air fly from Auckland to Vientiane and Luang Prabang in Laos, with three flights a week from Singapore to each destination.
Further information: See whc.unesco.org.