U-turn

On a narrow mountain road a man sees a police car driving uphill backwards.
– Hi guys. Why are you driving backwards?
– Because we are not sure that we will find a place to make a u-turn on the top of the mountain.
After one hour the same man sees the same police car driving downhill backwards again.
– But guys, why are you driving backwards again?
– We found a place to make a u-turn up there.