Road Trip

A couple of weeks ago Mr. and Mrs. RiddleDude took a trip up north to see the foliage, and while we were way up north there, we decided to visit our a friend, who lives way up in the boondocks with his ice pick and his flock of sheep and all that. And while we were sitting around he says, “You know, guys, there’s a road right near my house that runs directly north and south.” We said, “Well, sure that’s no big deal.” And he says, “Well, I can put my car on this road and point it north, drive a mile and when I’m done I’m a mile south of where I started.” And we said, “Get out of town.” He offered to show us and he did. So how did he do it?