The Elephant Circuit by Robert A. Heinlein - The exposition was easily the biggest John Watts had ever seen, and he'd seen them all. Yet, besides its size, there was something else strange about this fair–it was just a little out of this world!

Rain streamed across the bus's window. John Watts peered out at wooded hills, content despite the weather. As long as he was rolling, moving, traveling, the ache of loneliness was somewhat quenched. He could close his eyes and imagine that Martha was seated beside him.