High Quality Content by WIKIPEDIA articles! The Isthmus of Tehuantepec is an isthmus in Mexico. It represents the shortest distance between the Gulf of Mexico and the Pacific Ocean, and prior to the opening of the Panama Canal was a major shipping route known simply as the Tehuantepec Route. The name is taken from the town of Santo Domingo Tehuantepec in the state of Oaxaca, which in turn comes from the Nahuatl tecuani-tepec ("jaguar hill").