and is prohibited in the Commonwealth of Pennsylvania. At certain intersections, left-turning traffic may be given precedence over straight-moving traffic in a regulated (and thus legal) manner, via the use of protected turn signaling. In Ontario, Canada, such a turn is considered stunt driving under the provincial Highway Traffic Act. Origin Many of Pittsburgh's roads are narrow streets with only a single lane in each direction, and most intersections lacking left-turn-only lanes. If a car is attempting to turn left, no other cars behind it can proceed through the intersection. Allowing the left-turning car to proceed first through the intersection gives that driver a chance to get out of others' way, allowing for smoother flow. See also Pittsburgh parking chair Michigan left References Hazardous motor vehicle activities Culture of Pittsburgh Driving techniques