Gravity Hill - Pittsburgh, Pennsylvania

A gravity hill, also known as a magnetic hill, mystery hill, mystery spot, gravity road, or anti-gravity hill, is a place where the layout of the surrounding land produces an optical illusion, making a slight downhill slope appear to be an uphill slope.

Thus, a car left out of gear will appear to be rolling uphill against gravity.

There are hundreds of recognized gravity hills around the world.

ball on gravity hill
Image: Mysterious Road Defies Gravity in Pittsburgh
Info: Wikipedia
Graphic: @maptheclouds