To solve a problem in which a terrible accident is frequently caused by contact with a guardrail or protective barrier of a road during inattentive driving, drowsy driving or drinking driving, by making the guardrail and protective barrier in a structure with extremely reduced frictional resistance which is expected to allow a vehicle to travel along a wall surface reducing the rebound of the vehicle on a collision surface and hence the chance of causing a spinning or overturning accident.

As a means for solving the problem, this plan proposes the protective barrier, a protective fence and the guardrail of the road of arranging a rotary body so as to rotate in the rotational direction of the vehicle.