(Sorry: above links in Slovak.)
Can someone explain this to me? Is it a hoax?
Dear LanceBaynes, maybe you shouldn't expect that all users speak almost perfect Slovak on this server - even though you may be right with some of us. ;-)
shows that the cars are moving exactly as the altimeters and level indicate. There's nothing anomalous about that place. Markíza TV has already aired an official spot explaining that this story is just a hoax. See also TV Noviny.sk,
When the cars move spontaneously, they reduce their altitude by 150 meters or so. And I think that this stunt has been copied from some foreign places where people have equally nonsensically claimed that cars are moving uphill. For some list of "gravity hills" (with the same claimed property) in the world, see
The Wikipedia link explains that all "gravity hills" are optical illusions. In general, some of these "mystery spots" may even be cleverly engineered tourist attractions:
Optical illusions are often not accidental - they're deliberately fabricated by houses built with wrong inclinations, and so on. Especially in the case of the most famous mystery spot near Santa Cruz in California (where I've spent half a year) opened around 1940, see the Wikipedia link above, this has been designed as a business project. You can be pretty much sure that everyone involved in the promotion of that place in Slovakia is either a naive simpleton or a participant in the hoax.
Quite generally, water is not magnetic so it couldn't be affected, and the non-verticality of the gravitational field cannot exceed a certain tiny angle anywhere on the globe. Even near Mount Everest, which is huge relatively to anything you find in Slovakia, the angle between the direction of the gravitational field and the direction towards the center of the Earth is much smaller than a degree - while the hoax in Lačnov claims that the angular anomaly is of order dozens of degrees which is clearly nonsense.
Claims that the surprising effects are caused by "magnetism" are almost on par with the claims that they're caused by "paranormal phenomena": both of these claims would manifestly contradict even elementary basic-school science.