Trifter

When I was a young lad in Minnesota, I used to like to go through large department stores on my way home to get out of the stinging cold and, ideally, shorten my path. But actually, the path I took was just as jagged as if I’d stayed outside. Although I did manage to warm up for a few minutes, I probably didn’t make my trip any shorter.

Imagine you’re in the downtown business portion of any large city, such as New York City’s Manhattan, where the streets are laid out like a grid. Each block is the same size, and tall buildings prevent you from moving anywhere but along these blocks — unless you can leap tall buildings in a single bound, of course. Likewise, cars must follow the streets that separate these blocks. The distance from point A to point B, unless both points are on the same block, is going to be longer than if you could travel. Because Manhattan is an excellent example of this restricted movement, geographers refer to distance measurements in this environment as Manhattan distance.

To travel from point A to point B, you need to follow the edges of the blocks. By moving along the blocks, you have to travel a much larger distance than if you could travel the straight-line distance. This grid structure allows many possible paths from one point to another, but each path covers essentially the same distance.