I believe some highways are purposely built slightly crooked (like an S) over long flat stretches, to keep drivers more engaged and less likely to fall asleep.

I believe some highways are purposely built slightly crooked (like an S) over long flat stretches, to keep drivers more engaged and less likely to fall asleep. I'm not sure if there are any that are built that way to look straight on Mercator projection. Of course, there are large parts of the world where the population density isn't worth doing such a thing, and you have quite long roads that are perfectly straight from the driver's point of view.