Natural Wonders: Gravity Hills

There are peculiar spots around the world where the laws of physics do not seem to apply. What goes up does not come down in areas known as gravity hills.

A gravity hill is where a downhill section of road appears to be going uphill. If you place your car in neutral, the vehicle will start to move, as if it is rolling uphill.

Magnetic hill, Ladakh. Photo: Shutterstock

 

Because of this illusion, travelers have considered gravity hills to be spots of heightened paranormal and extraterrestrial activity. Urban legends speak of the spirits of murdered Native Americans or victims of car accidents who push these cars up hills. In the past, scientists incorrectly hypothesized that the anomaly had something to do with the Earth’s magnetic poles. In reality, it is an illusion that occurs in particular surroundings because of the brain’s inability to process what is really going on. 

Needed: no horizon, no buildings

What tricks your eyes into thinking you are looking uphill is the lack of a proper horizon. The horizon line is obstructed or curved away from view. In these conditions, gauging a slope is sometimes difficult. Leaning objects like trees can trick you into thinking that a flat or downward slope trends upward. 

Magnetic Hill in New Brunswick. Photo: Laurie Piskun

 

To understand the phenomenon, geophysicists and surveyors studied the land and its gradients. They discovered that the illusion occurs when the land tilts in one direction and the road goes in the same direction but at a lesser angle. Gravity hills are found mostly — though not always — in green areas where the road is fairly narrow. No buildings should be in sight. Buildings provide a point of reference that your brain can use to process the image. 

Gravity hills exist all over the world. You can find one in almost every country. The United States has around 52 of them, for example, and the United Kingdom has six.