Mexico's largest and most profitable railroad. Ferrocarrill Mexicano "Ferromex" is the largest railroad company in Mexico and has the widest coverage. Ferromex has a network of 8,111 kilometers of tracks that covers approximately 71% of the Mexican territory. Ferromex lines connect to five border points with the United States, and also connect to four ports in the Pacific Coast and two in the Gulf of Mexico. Ferromex is controlled by Grupo México 55.5%, Union Pacific 26% and Grupo Carso-Sinca Inbursa 18.5%.