The Andean municipality, 240 kilometers south of Santiago, has opened the country's first UFO trail, a 30-kilometer long stretch that takes in a supposed landing site for flying saucers and optimal lookouts for extraterrestrial craft.
Sernatur, Chile's tourism service, is backing the initiative.
"We support the creation of this UFO trail because experts say that it is a 'hot zone' for watchers," the service's director, Oscar Santelices, told AFP.
However, just in case hordes of foreign tourists of the terrestrial variety turn up expecting to get a close encounter of a first, second, third or ? heaven forbid ? fourth kind (alien abduction) out of their trip, Sernatur had a bucket of cold water.
"In no way can we guarantee that a tourist coming to San Clemente will see a UFO," it said in its brochure.
The Chilean town has long been an unofficial destination for UFO-watchers in the know, though mainstream curiosity-seekers looking for a bit of interplanetary mystery have been more often drawn to neighbouring Peru to see the Nazca Lines, those centuries-old gigantic representations of animals in a desert which can only be fully appreciated from the air.
UFO researchers say hundreds of UFO sightings have been reported in San Clemente since the mid-1990s.
Rodrigo Fuenzalida, president of the Chilean Grouping for UFO Research (AION), said between January 1995 and the middle of 1996 there was around one sighting per week.
The last unidentified flying object spotted was in the third week of February this year, he said.
"It was an orange object located about 400 meters in the distance, with oscillating movements," he said.
A site of special interest is a flat zone of huge volcanic blocks known as El Enladrillado, 60 kilometers from San Clemente and at an altitude of 2300 meters, which locals claim is a UFO landing pad.
"There, sightings have been made of shining spheres going into the water and into wooded zones without any human explanation," Fuenzalida said.
El Enladrillado, which can only be accessed after hours of trekking over rough terrain, forms the central part of the UFO trail.
Other points along the path include signs detailing sightings, as well as restaurants, camping sites, hostels and cabins to serve hungry or weary Earthlings, Juan Carlos Cerro of the local tourist office said.