Sierra Madre Oriental

The Sierra Madre Oriental is a major mountain range in northeastern Mexico that runs generally northwest-southeast roughly parallel to the Gulf of Mexico. It is one of Mexico’s principal mountain systems and spans several states over many hundreds of kilometres.

The range is composed of rugged ridges, high plateaus and steep canyons; many areas offer hiking, climbing and scenic drives. Vegetation changes with elevation, from subtropical lowland forests on the eastern slopes to pine-oak and mixed mountain forests higher up, supporting diverse birdlife and endemic plants.

The range is a long-lived geological feature that has influenced human settlement, transport and climate patterns in northeastern Mexico; indigenous groups and later colonial routes followed river valleys and mountain passes. Over time the mountains have been important sources of timber, water catchments and grazing land.

The Sierra Madre Oriental runs roughly along eastern Mexico from the northern states near the Rio Grande down toward central Mexico, forming the eastern backbone between the coastal plain and the central Mexican Plateau.

• Extent: The range runs roughly parallel to Mexico's Gulf coast for many hundreds of kilometres and forms an important climatic divide between the coastal lowlands and the inland plateau.
• Elevation and ecosystems: Elevations commonly exceed 2,000 meters in parts of the range and support extensive pine-oak forests and endemic mountain flora.