Prudencia Acosta is one of this small mountainside town's biggest attractions.
Dressed in a dark brown shawl and cape, clutching a red carnation in her wizened hands, she stands propped against a wall to receive curious visitors.
Prudencia died more than 10 years ago.
She is one of San Bernardo's "living dead"--corpses that mummify naturally in their coffins, defying the normal process of decomposition in a phenomenon which has baffled townspeople and drawn hundreds of curious visitors.
Gravedigger Eduardo Cifuentes was the first to notice the mummies when he began work in San Bernardo 15 years ago.
"The burial pit was full of bodies," he said. "I didn't like stepping on them because they were humans like us so I started organizing them."
The mummies are housed in the underground crypt of the local cemetery, a green plot of land with grazing cows on the side of a hill with a view of the surrounding mountains.
In front of one of the rows of white, boxlike tombs is a metal trapdoor, which opens to reveal a flight of steep steps leading down to a small dank chamber.
About two dozen bodies are arranged in a standing position around the walls of the room. A man in an earth-colored suit next to the entrance greets visitors, a large wooden crucifix hanging from his neck underneath a stylishly knotted tie. His hairy head tilts back at a grotesque angle.
Some of the faces wear a peaceful, calm expression while others are contorted with the grimaces of painful final moments.
Bodies had mummified naturally in the village for years, Cifuentes said, but no one had paid them any attention. "I liked the idea of keeping them for posterity," he explained.
The passage of time has turned the mummies' clothes and their skin to an almost uniform earth-brown color.
A well-preserved severed hand lies on the head of one of the crypt's occupants, placed there for safekeeping after dropping off the arm to which it was attached.
The best-preserved of the bodies stands inside a glass case, neatly fitted out in jacket, tie and trousers, with only an oddly pale face and sunken eye sockets giving him away as a corpse.
The mummies have begun to draw visitors from other parts of Colombia and from abroad to San Bernardo, an agricultural town of 17,000 people about three hours' drive south of the capital Bogota in the foothills of the Andes mountains.
As yet no scientists have made a study of why some townsfolk mummify in their coffins instead of turning to dust. Local people say the only other site in Latin America with natural mummification is the central Mexican town of Guanajuato, where villagers cite underground gas and soil conditions as the secret.
That explanation does not work in San Bernardo because bodies here are buried in chambers above ground and do not come into contact with the earth.
Local people offer a variety of explanations ranging from the purity of the water to the lack of chemical additives in the food, but the most commonly heard is the presence of two unusual fruits in the local diet.
"I think it has a lot to do with the food," said Helder Jose Roa, a worker in the cemetery. "People here eat a lot of 'guatila' and 'balu.' " Neither of the fruits appears in Spanish-English dictionaries but "guatila" is a deep green hard food about the size of an orange with small thorns on its skin. It is extensively used by villagers in soups and other dishes after peeling and boiling.
"Balu" looks like a giant green bean pod, which is opened and its outsized purple beans extracted to cook and mash into flour for cakes.
The mummies' fame is set to grow. Mayor Antonio Acosta, eager to cash in on the tourist potential of his town's dead, has ordered the construction of a special museum that is nearing completion behind the cemetery.
Eight of the best-preserved mummies will be displayed there on concrete slabs under glass for visitors, while a small amphitheater within the building will give visiting professors a chance to lecture students on the strange phenomenon.
Not all the townsfolk are happy with the idea of a future as a mummy under glass in a museum.
"Some people say they're not going to have a bunch of kids coming along and poking fun at their dead relatives," said Claudia Garcia, a San Bernardo housewife.