A vehicle is adaptable to various terrains. The vehicle includes a frame and two rolling sets connected to the frame. Each of the rolling sets includes two legs pivotally connected to the frame, two casters, a pin and a wheel. Each of the legs defines a slot. Each of the casters is connected to one of the legs. The pin is carried by the frame and extends through the slots so that the motor is moved when the legs are pivoted. The wheel is operably connected to the motor so that the casters and the wheel always grip the ground firmly regardless of whether the casters are up or down.