Around the world, there are areas that have gained a reputation for being strange and mysterious because gravity appears to not work the same there as it does in an ordinary environment. Such “mystery hills” or “mystery spots” attract visitors and scientists who wish to experience the effect for themselves: up appears to be down, level ground is askew. The local tales attempt to explain the disorientation as resulting from a gravity anomaly, a deposit of iron or igneous rock that generates a magnetic field, a space-time disruption, or even invoke paranormal entities, aliens or secret technology. Is it true that these baffling mysteries require scientists to rewrite physics? Should people and animals avoid such bizarre places? The answers are surprisingly available and forthright, but they are displaced by the dramatic legends.
Gravity Roads and Mystery Hills
Hundreds of places known as Gravity Hill, Magnetic Hill, or Spook Hill (or similar names invoking confusion or wonder) exist around the world. These are low-traffic roadways in the countryside where, if you stop and put your car in neutral, it appears to roll uphill. Or, a ball placed on the surface will move in the opposite expected direction. Water appears to flows against gravity. Gravity Hill is a location promoted by the Bedford County tourism board in Pennsylvania. It is one of many “strange slopes” around the world where an observer visually perceives an apparent slope based on surrounding cues. Objects moving under gravity alone appear to travel in the unexpected direction – startling observation that freaks people out.
Wikipedia has a list of many of these places, at least the ones that have been marketed to the public to check out and experience for yourself. The U.S. has the most locations, possibly because this version of Wikipedia is in English. Or, more likely, mystery hills are very much an American phenomenon associated with leisure car driving that has been popularized for several decades. On pleasant weather weekends, these mystery hills will be busy with cars in a line having a go at defying gravity or, as the local stories suggest, experiencing a magnetic or mysterious force pulling the vehicles uphill. Mystery hills are never in an urban area but are narrow, almost straight, paved roads located in hilly landscapes. They are frequently demarcated by paint lines on the roadway that signal where to stop and put the car in neutral. Or, signage indicates instructions.
The media loves stories about mystery hills and frequently promote misinformation about them. Tourist sites highlight mystery hills for a worthwhile visit. News outlets often mention that some scientists are looking into solving the “mystery” of the site but such scientists mentioned often seem incongruously ignorant of basic physics and geology.
In 2010, at Kalo Dungar in Kutch, Gujarat, India, locals noticed that their cars appeared to roll down the scenic hill at startling speeds – 80 kmph – without a discernable cause. Speculation arose that an undocumented magnetic effect was pulling the cars down the hill. A team of experts from the Gujarat State Disaster Management was called in to study the phenomenon. A study later completed confirmed that the steep slope was the sole cause of the acceleration. No magnetic forces were needed.
Why would magnets be invoked at all to explain these mystery hills at all? Magnetic forces do not work on non-metallic substances so a magnetic force has no effect on water or plastic balls that appear to roll uphill. A magnetic effect would be easily noticeable and measurable, not hidden. But, most people aren’t all that clear how magnetics work.
At Magnetic Hill on the Isle of Man in the UK, if the magnetism from local iron deposits isn’t the cause, it’s the little people (fairies) that push the cars uphill. In other places, it’s ghosts. It’s difficult to keep count of the many stories that explain the anomalously moving cars as the product of ghostly hands at work. The stories sometimes relate that those who died from an accident on that very spot are pushing your car to safety so you don’t suffer their fate. Alternately, the ghosts of those who perished at a nearby spot might supposedly pull cars towards them for help. Spook Hill in Lake Wales, Florida promotes the legend of a Seminole chief who was killed in a battle with an alligator and was buried alongside what later became the “haunted” road. But that’s not the only ghostly tale there! A dead pirate buried at the foot of Spook Hill was said to come out and move cars that parked on his grave. Ghost children will push your car off railroad tracks in San Antonio or out of harm’s way in Lewisberry, PA. To be clear, there were no documented accidents as described in these locations but the story persists.
The truth of mystery hills is well-known to be an optical illusion. Scientific experts in visual perception confirmed that the brain is guided by spatial frames of reference we see. When those frames are missing or askew, we get confused and things feel odd. Situated in hilly surroundings, the horizon is obscured on the straight stretch of a gravity hill road, so we lose our horizontal reference and instead use local cues to judge slopes, which can be misleading because there aren’t many. Trees or walls in the surrounding area may be off-vertical making a downslope look like it is level or inclined upwards. Several scientific papers demonstrated this effect of visual illusions.
As with Gravity Hill in Pennsylvania, a slight downward stretch between two strongly downward stretches can be perceived as uphill or horizontal. Or, the apparent slope is opposite to the actual slope. Use of a level will confirm the correct inclination. Maps will clearly show the topography. The measurements have been checked, the elevations are not out of whack, water doesn’t really flow uphill, but your eyes will definitely fool you. The often remote locations and lack of structures for horizontal reference increase the eerieness of the mystery hills. The illusion is so convincing, it’s difficult for people to believe it, so they feel the need to invoke more dramatic explanations. They draw on their ideas of pulling from gravity or magnets instead. And they may believe the exotic sciencey-sounding explanations related to an underground geological cause (that they can’t see or confirm). Or, they want to believe in ghost stories or anti-gravity mumbo-jumbo.
When I was a kid, the local amusement park had a “crooked shack” that was constructed at odd angles so that when you walked through it, you were disoriented and confused but it was highly amusing. Many more of these crooked shacks exist as tourist traps across the world. They are variously described as being located above a gravity anomaly or in an energy “vortex” where space-time does not behave. A “vortex” (used in the paranormal sense), like the famous “vortex” areas in Oregon, Montana, and Sedona, AZ, as well as geographically legendary “vile vortices” such as the Bermuda Triangle and the Devil’s Sea, have been characterized by sciencey-sounding proponents as locations where some wild earth energy thing creates extraordinary observations. They are often linked to nodes of ley lines, alien charging stations, giant underground machinery, and wacky alternative physics.
You’ll have to pay to visit most crooked shack “mystery spots”. A famous one is in Santa Cruz, California. The tour guides say the “gravity house” is the product of a circular anomaly about 150 feet (46m) in diameter where gravity misbehaves. Here is a ridiculous attempt at an explanation from their website:
Some speculate that cones of metal were secretly brought here and buried in our earth as guidance systems for their spacecraft. Some think that it is in fact the spacecraft itself buried deep within the ground. Other theories include carbon dioxide permeating from the earth, a hole in the ozone layer, a magma vortex, the highest dielectric biocosmic radiation known anywhere in the world, and radiesthesia. Whatever the cause is, it remains a mystery.The Mystery Spot (Santa Cruz)
*SPOILERS* No, it's no mystery. That's a whole lotta bullshit in one paragraph.
The Santa Cruz Mystery Spot was listed as a California Historical Landmark (#1055) on August 22, 2014. It was not listed because of its natural wonder, though. It was notable as the first (1941) and most significant “tilt-box” or “gravity house” roadside attraction in California. It was certainly not the last. These types of tourist spots became popular in the mid-twentieth century.
Originally, tilt-houses were the product of the Great Depression era, when people needed cheap entertainment. Local tales notwithstanding, they have little to do with any physical anomaly. They are cleverly engineered structures designed to distort the architecture – where normal visual references are hidden, and distorted objects are added to enhance the effect. People stand at weird angles and experience a sensory illusion that can induce vertigo, nausea, or it may be entirely enjoyable and fun. Visitors are primed to be astounded and confused but discouraged from lingering too long in the structure to do any measurements. The exaggerated story of a physical anomaly that “baffles” scientists adds to the atmosphere. The illusion effect is so powerful that people buy a nonsensical incorrect explanation.
But what of the Saint Ignace Mystery Spot (Michigan) where the story goes that surveyors that found a piece of land that caused their equipment to malfunction – and nothing would register as level? Or of the messed up compass readings and weird feelings experienced at the Santa Cruz spot?
Gravity anomalies exist all over the world due to differences in density of the material underground, but they aren’t detectable by the average person, only by sensitive instruments. In order for a person to feel a gravity difference, or to see it affect a large object, it would have to be far more of an effect than could be accomplished on the earth’s surface. A compass will go wonky near a magnetic anomaly or an unnoticed electromagnetic field effect. (EMFs are everywhere in the modern world.) No hidden magnetic force can pull a car uphill. Various strange feelings are all too easily induced, especially when a person is primed by an eerie story about what weirdness to expect.
Scientists can conclusively demonstrate that no gravity, magnetic, or otherworldly physical effect is necessary to produce mystery spots or hills. They can recreate the illusions in a lab to show how convincing the perceptual illusion is. So, this spooky topic is more about geography and perception than geology or the paranormal. While most people are at least aware that these locations are an optical illusion, they still would rather indulge in the tales of the paranormal or natural anomalies that are associated with such locations. Making an attempt to undertake a challenge in response to local folklore is called “legend tripping”. It’s commonly associated with visiting haunted places or doing a task that will bring forth some nasty entity or open a portal to hell. In the moment, any surprise or coincidental happening will result in people freaking out. The legend tells you what might happen but the moment that something strange does happen can be exhilarating. The rise of websites and social media promotes mystery places. Visiting mystery spots or mystery hills is a form of legend tripping.
Mystery spots and hills are important features of the local community. With the various legends, we see how they fortify cultural identity, reinforce a specific sense of place, and they may even give people an almost spiritual experience. This is one reason why the real explanation is often ignored. I say that the truth about the mystery does not ruin the fun; it’s still amazing.
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