From Wikipedia

At a superstreet, all traffic on the side road must turn right, where it can access a U-turn ramp. Traffic on the main road can turn left directly. The opposite applies for countries that drive on the left.
superstreet, also known as a restricted crossing U-turn(RCUT) and a J-turn,is a type of road intersection that is a variation of the Michigan left. In this configuration, traffic on the minor road is not permitted to proceed straight across the major road or highway. Drivers wishing to turn left or go straight must turn right onto the major road, then, a short distance away, queue into a designated U-turn (or crossover) lane in the median. When traffic clears they complete the U-turn and then either go straight or make a right turn when they intersect the other half of the minor road.

This requires four traffic light-controlled intersections, and most traffic must pass through two of them, but each light has only two phases, greatly increasing average traffic flow; there is no need for numerous left-turn phases where most traffic is waiting for only a few cars to clear the intersection.

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