Sad how close to true this is. I used to work in transportation, and at least the USA* the figure is about $10-40M per mile, with rural highway being cheaper and urban highway being more expensive. So $1.6M really could buy you as little as 64 meters of freeway. (Or as much as 1/4 km!)

* Which, I should mention, has a bit of a tradition of cheaping out on the construction. Why worry about the higher maintenance costs when that's going to be your successor's problem? Better to kick that can down the road and brag about how much taxpayer money you're "saving". Ahh, the beauty of the spoils system.