Pittsburgh Left
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The "Pittsburgh Left Turn" (typically referred to simply as the "Pittsburgh Left") is a colloquial term for a rule of the road that is obeyed almost exclusively in the Pittsburgh, Pennsylvania, area. It refers to the counter-intuitive practice of giving left-turning vehicles precedence over vehicles going straight through intersections, which improves traffic flow.
The "Pittsburgh Left Turn" applies when opposing lanes of traffic are both stopped at a red traffic light. If you are waiting to proceed straight through the intersection, while the car stopped at the light in the opposite direction from you has its left turn signal on, the driver of the opposing car expects you to allow them to make the left turn before you proceed straight.
This tradition began because most streets in Pittsburgh are narrow and often filled with parked cars, allowing for only one lane of traffic in each direction. Therefore, someone waiting to turn left at a light is going to hold up their entire lane of traffic, unless someone lets them make their turn.
The tradition is not only tolerated in the Pittsburgh area but is actually expected by longer-term residents, despite the authorities' attempts to discourage it. Few other areas of the country have this tradition.
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