The riddle
What Goes Through Cities and Fields but Never Moves?
Goes, but stays
Roads do not travel. The cars, bikes and walkers on them do, and the traffic changes by the hour while the road stays exactly where it was. A road "goes" in the sense that it extends from one place to another and passes through the places in between. The riddle takes that everyday phrase literally and asks what moves. Nothing in the road itself does, which is why the question sounds contradictory until the answer is spoken.
How much road there is
The Federal Highway Administration reports more than 4 million miles of public roads in the United States in its 2019 statistics, a figure that includes city streets, rural roads and highways. That is enough to circle the earth at the equator more than 160 times, since the equator is about 24,900 miles around. Driving every one of those miles at 60 miles an hour without stopping would take more than seven years. A path that long stretches through both towns and farmland.
The word road
The English word road comes from an Old English word for a riding or a journey, and the idea of travel is in it from the start. The riddle plays against that meaning, since a road records journeys without taking one. Parts of a road have names too: the shoulder is the strip along the edge, and a median separates lanes going in opposite directions. None of them moves either.
A riddle with many wordings
Different tellers say "towns and over hills" or "cities and fields", and all of them mean the same thing. The answer does not change with the list of places, because the thing being described is the road, and any town or field along it is only scenery.