Odysseus, on his journey home to Ithaca, was visited by a ghost. The ghost tells him that once he reaches his home, once he slays all his enemies and sets his house in order, he must do one last thing before he can rest. The ghost tells him to pick up an oar and walk inland. And keep walking until somebody mistakes that oar for a shovel. For that would be the place that no man had ever been troubled by the sea.