Sierra Madre de Oaxaca

The Sierra Madre de Oaxaca is a mountain range in southern Mexico. It begins at Pico de Orizaba and extends in a southeasterly direction for 300 kilometers until reaching the Isthmus of Tehuantepec. Peaks in the Sierra Madre de Oaxaca average 2,500 meters in elevation, with some peaks exceeding 3,000 meters.

The eastern slopes of the range are wetter, intercepting moisture-laden winds from the Gulf of Mexico. A number of drier valleys lie to the west, in the rain shadow of the range. The Sierra Madre de Oaxaca pine-oak forests lie above 1600 meters elevation. The humid Oaxacan montane forests lie below 1600 meters elevation on the eastern slopes, above the Veracruz lowlands. To the east, the xeric Tehuacan Valley matorral occupies the Tehuacan valley to the northwest, the Jalisco dry forests occupy the upper basin of the Santo Domingo River, which lies in the rain shadow of the Sierra, and the Southern Pacific dry forests lie to the south along the Pacific coast, extending into the upper basin of the Tehuantepec River and the Valley of Oaxaca.