Though The Comedy of Errors takes place in a single location, the characters come from all corners of the earth. Though they all happen to currently be in one spot, they do a fantastic job of relating their worldliness by using geography as a motif in the play. Geography symbolizes not only where you are, but where you’ve been and where you intend to go.
Egeon frames the whole play with a discussion of geography. He knows he is a stranger to Ephesus, but he explains that his work took him all over the world, and his traveling life as a merchant once had him held in esteem as a well-respected and wealthy man. He is quick to note that though he is being treated as a common criminal in Ephesus, that’s not actually who he is. The downturn in Egeon’s fortunes coincides with his travels, as he describes spending time "in farthest Greece, roaming clean through the bounds of Asia." He only came to Ephesus as he was heading homeward, and he quickly equalizes Ephesus with any other city by describing it as not unlike "any place that harbors men." To Egeon, the world has simply become a place filled with indistinguishable cities, as each city might hold his children. Equally of interest, as Egeon can find his sons nowhere – Ephesus is as good a place as any to die. Because his children are nowhere to be found in it, the world has become a small and suffocating place for Egeon. What’s important to him is where he’s been, as he doesn’t plan on going anywhere farther.
By contrast, to S. Antipholus, the world sprawls endlessly. What’s important about S. Antipholus is where he imagines himself to be going, and what he thinks can find there: at any corner, he might come upon his brother and mother. Like Egeon, S. Antipholus is committed to searching all over the world for his family, but, unlike Egeon, he hasn’t yet given up. The vastness of the world may be daunting at times, but it is like any great big prospect – it is continually exciting because it is also full of possibility. You’ll note S. Antipholus, though he says, "with long travel I am stiff and weary" (1.2.15) is set to hit the streets in Ephesus and observe what there is to see. If his dad is a weary businessman flying in boring first class, S. Antipholus is an Australian backpacker who finds himself alone in a hostel during a blackout in Amsterdam. Except he’s traveling to "discover himself," so he’s like a singer-songwriter backpacker.
The point is, Egeon and S. Antipholus are very different men. Egeon entered Ephesus and immediately found a death sentence, while S. Antipholus found a city that opened up to him, rich with dinner invitations, willing women, and even gold jewelry. Ultimately, though, enough is enough and S. Antipholus chooses to walk away from all of these things, even though they seem like blessings. Instead, he’s happy to move onto the next place as soon as possible – even though this place seems enchanted (for better or worse). Indeed, S. Antipholus shows his optimism by escaping to another location. Again, the world is as wide as his ship can sail and his money can take him, which is pretty wide.
Finally, there’s a bawdy nod to the fact that knowing one’s geography is a good hint that one knows the ways of the world, or the facts of nature. S. Dromio and S. Antipholus have a good laugh at Nell’s expense by comparing her girth to the breadth of the planet. In this little episode, if we were feeling particularly symbolic, we could talk about how "the mapping of Nell" is a farcical nod to the "woman as uncharted territory in the trope of the feminine mystique," but that might overcomplicate things. For our purposes, the less scintillating and more obvious idea is that women are as easily discovered, conquered, and departed from as any of the locations these young men can be privy to.