The US-Mexico border stretches 1,954 miles, with each mile hiding unexpected secrets. Discover a river forming an international boundary that runs dry for 200 miles, and a border fence mistakenly placed on the wrong side. Learn about a jaguar reclaiming American territory without a passport, and cities sharing sewage systems across nations. Explore vast sand dunes where the border remains invisible, without any fences or markers.

Join us as we delve into 50 of the most bizarre, surprising, and overlooked geography facts about the US-Mexico border. From the Pacific Ocean to the Gulf of Mexico, explore volcanic landscapes, international lakes, tunnels beneath the border, and rivers flowing in unexpected directions.

This is a geography tale like no other.