Sierra Madre del Sur
The Sierra Madre del Sur is one of the three main ranges of Mexico. The other two are the Sierra Madre Occidental and Sierra Madre Oriental. Where the Occidental and Oriential are north-south in orientation, the Sierra Madre del Sur tends to be west-east, rising on or near the southern Pacific coast. The range is not, however, clearly defined, as isolated massifs tend to rise in jumbled clusters throughout the region. The range continues into Central America, and its highest summit, Volcan Tacana (13,425 ft.), rises on the Mexico- Guatemala border.