A major hub for North American trade sits in the river bottoms near downtown Kansas City. Here, the sprawling Knoche Yard accommodates long rows of engines and rail freight. Some trains are reconfiguring their rail cars as they continue their routes from city to city. And south of Kansas City, at the site of a former Air Force base, containers carrying important freight are lifted on and off trucks as they interchange with intermodal rail service.

Some shipments at this Kansas City juncture are on a much longer journey, spanning Canada, Mexico, and the United States.

These rails mark the southernmost stop on the Canadian Pacific Railway (CP), which stretches from Montreal to Vancouver, reaches down through the Midwest, and terminates in Kansas City.

Missouri-based Kansas City Southern Railway (KCS) runs from Kansas City all the way to Mexico, connecting to terminals on both the Pacific Ocean and the Gulf of Mexico.

Canadian National Railway (CN), which ties to Canadian ports in Prince Rupert and Halifax, is also relatively close, as it passes east of St. Louis, where Kansas City Southern has a rail connection.

While numerous other rail line combinations also carry goods between the three nations, the rail connections here are particularly important and befitting its nickname: The NAFTA Railway.

“KCS is an important interchange partner to CP for a wide variety of products,” says Andy Cummings, manager of media relations for Canadian Pacific. “CP originates a train daily from Knoche Yard, which we operate jointly with KCS, with blocks of railcars for Davenport, Iowa, and St. Paul, Minnesota. From those two points, cars make connections for destinations in the Midwest and Canada. Additionally, CP handles unit trains to and from KCS, as our customers’ demand dictates.”

With these railways converging in and around Missouri, it’s very common to see trade between Canada and Mexico moving directly through the states.

“Quite a significant amount of cargo is moving on a joint CN/KCS or CP/KCS route from Canada through Laredo, Texas, and into Mexico every day,” says Doniele Carlson, associate vice president for communications and community affairs at Kansas City Southern. “The same is true in the other direction.”

Cummings says agricultural products, finished automobiles, and energy products are some of the most common things that travel along the Kansas City rail corridor. Carlson says crude oil and Canadian lumber are also major products coming through Kansas City.

With several international border crossings along the route through North America, these shipping lanes can sometimes become complicated. However, significant work is being done to improve both crossings.

Rail shipping was one of the focuses of the 2011 Beyond the Border action plan between Canada and the United States. In 2015, the countries signed a new pre-clearance agreement, which should yield improvements.

“This agreement will help facilitate the legitimate trade and travel that keeps our economy thriving as we maintain utmost vigilance to the security of our borders,” says Jeh Johnson, US secretary of Homeland Security.

Likewise, Carlson says Kansas City Southern and partner railways have been working to speed up crossings at the US-Mexican border. These improvements are helping trains keep moving as they cross the rail bridge between Laredo, Texas, and Nuevo Laredo, Mexico.

“The US-Mexico border crossing has become increasingly efficient in recent years,” she says. “Generally, freight moves across the border seamlessly, having been customs cleared for its final destination—north and south—in route to strategic operational locations.”