The question is: What can cross an ocean without ever getting wet?
At first, you may picture airplanes, bridges or something floating above the water. But the classic answer is something that can travel across the ocean while remaining safely inside another object.
The answer is: a letter or postage stamp.
A letter can cross an ocean inside a mail plane or ship without the letter itself ever touching the water. A postage stamp attached to that letter can make the same journey without getting wet.
The riddle works because “cross an ocean” makes us imagine physically moving through the water. In reality, something can cross from one side of an ocean to the other without ever making contact with it.
