The modern face of Mexican railroading: In February 2004, a southbound manifest train departs the siding at Agua Nueva, Coahuila, for the 2 percent climb to Carneros, on the TFM mainline south of Saltillo, Coah. Up front are a pair of SD70MACS; on the far left of the frame, you can see another Macs, DPU units that will be cut out at the summit.