This article analyzes the social and economic dynamics shaping the transversality of the Veracruz-Mexico-Acapulco trade route to Mexico City, in order to ensure the transfer of goods from Seville and the Caribbean via Veracruz, and those from the Manila Galleon arriving in Acapulco. The construction of these railways posed enormous challenges for the smooth flow of goods between the Atlantic and Pacific oceans, due to a constraining geography in which mountainous roads played a fundamental role. These challenges were overcome thanks to the emergence of new social actors such as the muleteers. Most of them were free mulattos, responsible for transporting goods from Veracruz to Mexico City and from Acapulco to the capital of the Viceroyalty. This is how these new groups emerged as key players, thus ensuring coast-to-coast commercial transversality.