isthmus of tehuantepec
isthmus in southern Mexico, between the Gulf of Campeche on the Gulf of Mexico to the north, and the Gulf of Tehuantepec on the Pacific Ocean to the south. From gulf to gulf the isthmus is 137 miles (220 km) wide at its narrowest part; and it is 120 miles (193 km) from the Gulf of Campeche to the head of Superior Lagoon, an inlet on the Gulf of Tehuantepec. The isthmus is a broad, plateaulike ridge. Its climate is hot, but Pacific winds often bring relief. The northern side is swampy and densely covered with tropical forest; the Pacific slopes on the south are drier.
Learn more about Tehuantepec, Isthmus of with a free trial on Britannica.com.