country mile

Rur. a great distance. The batter knocked that ball a country mile. I had to walk a country mile to the next gas station.

A distance that's farther than anticipated. Rural distances seem to be much longer than city folk think, so when a farmer says that the turnoff is “just a mile down the road,” that mile can stretch on interminably. The phrase used to be regularly used by baseball radio broadcasters to describe the distance of a long home run.