There's an annual celebration between the cities of Brownsville, Texas and Matamoros, Tamaulipas which could have been the precursor of this idea. It's called "

There's an annual celebration between the cities of Brownsville, Texas and Matamoros, Tamaulipas which could have been the precursor of this idea. It's called "Día del Charro" (Charro Day) https://en.wikipedia.org/wiki/Charro_Days https://en.wikipedia.org/wiki/Charro_Days. The two cities are in such good terms that even in the late eighties migration control was suspended one day so people could freely cross forth and back to see the parade starting in downtown Brownsville and ending in downtown Matamoros. This free crossing was discontinued due to federal laws, but the two cities remain as close as ever.