Spook Hill

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Spook Hill is a "gravity hill". An optical illusion where it seems vehicles and other objects roll uphill when they are actually going downhill.

The slope of a gravity hill is an optical illusion, usually with a completely or mostly obstructed horizon. Without a horizon, judging the slope of a surface is difficult as a reliable reference is missing. Objects one would normally assume to be more-or-less perpendicular to the ground (such as trees) may actually be leaning, offsetting the visual reference.