Moving walkways, or “people movers” as they’re sometimes called, can be found in most major American airports. And, at least in theory, they serve a pretty important function—moving a bunch of very rushed people, very short distances, a little quicker than they can on their own two feet.

The moving walkway is completely associated with air travel, but it turns out it was not invented to get you to your plane on time. In fact it  was originally seen as a form of mass transportation. Over the course of a century, a group of architects and engineers dreamed of turning the sidewalk into a magic carpet that could carry people all throughout the city.