El Paso, Texas / Ciudad Juárez, chihuahua

Together, known as "Paso del Norte." Over 2.7 million people, this binational region is the second largest metropolitan area on the México-United States border. The Juárez-El Paso region is the largest bilingual, binational work force in the Western Hemisphere. While U.S. politicians in 2016 often spoke of erecting a southern border wall, the United States had already built this wall between the sister cities in 2008.