People in Hong Kong drive on the left side of the road, but people in mainland China drive on the right side of the road. How do you switch them when they cross the Pearl River? Dutch design firm NL Architects proposes this figure-eight design that splits the lanes and reroutes both to the correct side of the road for each direction.
The bridge does exactly what the name suggests: It flips traffic around. The key here is separating the two sides of traffic, using a figure-eight shape. One side of the road dips under the other, funneling cars that were traveling on the left to the right (and vice versa), without forcing them to encounter head-on traffic at an intersection.[...]
Say, for instance, you're coming from Zhuhai. As you cross the bridge on the right into Hong Kong, the highway slopes downward to let you pass under the oncoming traffic. As it slopes back up, you reemerge on the left. No cars barreling straight at you. No concrete labyrinth to maneuver through. No sweat (and, ostensibly, no blood).
Link | Image: NL Architects