Since the mid 19th century, the paved portage road known as the diolkos has been central to interpreting the historical fortune of the city of Corinth and the commercial facility of its isthmus. In this article, I reevaluate the view that the diolkos made the isthmus a commercial thoroughfare by reconsidering the archaeological, logistical, and textual evidence for the road and overland portaging. Each form of evidence problematizes the notion of voluminous transshipment and suggests the road did not facilitate trade as a constant flow of ships and cargoes across the isthmus. The diolkos was not principally a commercial thoroughfare for transporting the goods of other states but facilitated the communication, transport, travel, and strategic ends of Corinth and her allies. The commercial properties of the Isthmus of Corinth subsist in its emporion for exchange, not in a road used for transshipment.