The highest point is Cerro El Hongo with an elevation of 1,786 metres (5,860 ft) at a location of 24° 34′ 20″ North Latitude and 99° 04′ 24″ West Longitude.

Desert thorn shrub (Tamaulipan matorral) is the most common vegetation in northeastern Mexico and covers the driest areas in the Sierra up to 1,600 feet (300 to 500 m) in elevation.

In the cooler temperatures at the higher altitudes in the Sierra oak-pine forests are characteristic at elevations of more than 800 meters (2,600 feet).

The riparian forests feature species such as hickory (Carya palmeri) more characteristic of the United States than Mexico.

[3] The Sierra de San Carlos has a semi-arid climate with hot summers and mild winters.