How We Get Around

Via Infrastructurist. Pictures of different highway interchanges.

The Cloverleaf - a classic, but it has fallen into some disfavor among traffic engineers because it causes weaving because cars are entering and exiting in the same lane. It also doesn’t handle large traffic volumes as well as some other configurations (for example, stacks).

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The Stack - A vertically layered arrangement of highways and connecting elevated ramps. The number of levels varies and go as high as six (though three and four are more common). Stacks are expensive to build but very efficient for high traffic volumes. This example is in Shanghai, but there are many stacked interchanges in the US:

The Braid - This Maryland interchange is a stack design, but what’s unique about it is that the north and southbound segments of I-95 and east- and westbound segments of I-695 are actually braided over each other briefly in the middle of the interchange. (See a diagram here.)

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