Access to Pic de Bugarach, the place some new agers believe will be the only refuge from the Mayan apocalypse, has been blocked by French authorities - meaning no one will be spared when the world ends on 21 December if predictions are correct.
Although scientists have insisted the world will not end on that date, some believers maintain that the apocalypse is approaching.
In a final grab at hope, however, new agers say that when the world ends, the mountain will open up and aliens will come out in spaceships to save humans who live near the mountain.
Police have banned access to the mountain and surrounding village in anticipation of an invasion of people including doomsday believers and curious journalists.
Eric Freysselinard, a senior French official, said: "We are expecting a few visionaries, a few people who believe in this end of the world, but in extremely limited numbers.
"We are expecting greater numbers of people who are just curious, but in numbers we cannot determine. Above all, we are expecting lots of journalists."
The mountain is being guarded by 100 police and firefighters and Freysselinard has also put controls in place for people approaching the tiny village that sits at the foot of the mountain.
Some people believe that the world will end on 21 December because that is the date Mayan calendar ends. Theories about how the world will end range from the Earth colliding with another planet to a black hole opening up and swallowing the world.
Although some sceptics said the Mayan prophecy about the end of the world was simply a translation error, an Ipsos survey in May found that one in seven people believe the world will end at some point during their lifetime.
One in 10 think the Mayan calendar marks the apocalypse and 8 percent admit they have experienced some sort of anxiety about doomsday.
China has the biggest proportion of doomsday believers, with 20 percent thinking the world will end. Germans are the leading sceptics, with just 4 percent believing the prophecy.