Reference: natchi86.blogspot.com/2014/05/south-korea-2014-day-2-jeju-mysterious.html
Dive into the mysterious world of optical illusions
This 200-meter-long road became famous for a miraculous occurrence in 1981 when a couple stopped to photograph a car in neutral driving up a hill. The road is actually downhill for about three degrees, but the optical illusion makes it appear to be going uphill as if the car is driving itself. The road has been dubbed "Dokkaebi Doro (goblin road)" because of its unusual appearance, and there is a statue of a horned Dokkebi face nearby. It is worth noting that spilled liquids enhance the optical illusion.