CN Rail now offers something it likely didn’t offer years ago: direct railway freight service between Canada and Mexico. So what? you might ask. CN’s lines have seamlessly linked Canada and the U.S. for over 100 years. And with Mexico forming America’s southern boundary, just how difficult is it anyway to trundle freight cars across the Rio Grande between Laredo, Texas and its sister city, Nuevo Laredo, Mexico?
Admittedly, it is easy, apart from the obligatory customs inspection. But that’s only because the distance between the rails in Mexico is the same as it is in both the U.S. and Canada: four feet, eight-and-a-half inches. If the track gauge were different, cross-border rail freight transfers would likely be much more difficult, given the necessity of having to shift box cars from standard-gauge wheels to, say, narrow-gauge ones. Freight transfer would also likely be far slower and much more expensive.
Moreover, as much as CN Rail would obviously like to extend seamless freight haulage south of Mexico into Central and South America, it can’t. For one thing, there’s no direct rail connection between, say, Argentina and Central America. And even if there were, it would be a mixed blessing, given the hodgepodge of track gauges. In Argentina, for example, the rails are five feet, six inches apart while in Brazil, they’re only three feet, three-and-one-quarter inches wide.
Indeed, the Mexico-Canada freight link is the longest such international freight link in the world that uses one gauge. Although railways have long linked Europe and Russia, the gauge isn’t continuous, nor is it the same between China and Russia. And although Turkey, Iraq, Iran, Afghanistan and China all use standard gauge, the decades-old warfare in much of that part of the world — particularly in Syria, Iraq and Iran — makes through freight service unlikely any time soon, if ever.