Cerro de la Silla, situated within the metropolitan area of Monterrey, Nuevo León, in northeastern Mexico, is a prominent mountain and natural monument. It derives its name from the distinctive saddle-shaped appearance when viewed from the west. Remarkably, despite its location in the adjacent municipality of Guadalupe, it serves as an enduring symbol of Monterrey.
Spanning an expanse of 60.5 square kilometers (23 square miles), this mountain comprises four distinct peaks: Pico Antena, Pico Norte, Pico Sur, and Pico la Virgen. Among them, Pico Norte (North Peak) stands as the loftiest at 1,820 meters (5,970 feet), while Pico la Virgen (Virgin’s Peak) is the most modest, with an elevation of 1,750 meters (5,740 feet).
Designated as a natural monument by the Mexican government in 1991, Cerro de la Silla serves as a favored recreational destination. Hikers frequently embark on a 5.3-kilometer (3.3-mile) trail to reach its summit, a challenging ascent that typically consumes approximately three hours. From this vantage point, visitors are treated to a panoramic vista of the city of Monterrey.
In the latter half of the 20th century, an aerial tramway known as the Teleférico en Monterrey was constructed on the mountain’s north side to provide more accessible access to this iconic landmark. Tragically, on the day of its inauguration, June 2, 1961, a fatal accident occurred, claiming the lives of five individuals, including the tramway’s designer, Jesús Fernández. Today, only the upper station of the tramway remains, despite several announced plans for its reconstruction, none of which have materialized.
Cerro de la Silla is a striking geological feature that provides valuable insights into the region’s geological history. It is part of the Sierra Madre Oriental mountain range and is primarily composed of sedimentary rocks. The geology of Cerro de la Silla can be understood through the following key aspects:
Formation and Geological History: Cerro de la Silla, like many mountains in the Sierra Madre Oriental, has its origins in tectonic processes. It was formed over millions of years as a result of the convergence of tectonic plates. The Sierra Madre Oriental itself is part of the larger Mexican Fold and Thrust Belt, which is characterized by complex geological structures resulting from the collision of the North American Plate and the Caribbean Plate.
Sedimentary Rocks: The mountain is predominantly composed of sedimentary rocks, which are layers of accumulated sediment that have undergone lithification (the process of turning sediment into rock). These sedimentary rocks provide valuable information about the ancient environments in the region. Fossils found within these rocks can help scientists reconstruct the past climate and ecosystems.
Layering and Stratigraphy: The sedimentary rocks that make up Cerro de la Silla are typically arranged in distinct layers or strata. Each layer represents a different period of deposition and can contain clues about the geological history of the region. Over time, these layers were subjected to compressional forces, leading to the folding and tilting observed in the mountain’s geological structure.
Tectonic Activity: The mountain’s geological features, including its distinctive saddle shape, have been shaped by tectonic forces. The uplift of the Sierra Madre Oriental and the associated folding and faulting processes have contributed to the current topography of Cerro de la Silla.
Mineralogy: While Cerro de la Silla is not particularly known for its mineral wealth, sedimentary rocks often contain various minerals, including quartz, feldspar, and calcite, among others. The mineral composition can vary depending on the specific rock layers within the mountain.
Erosion and Weathering: Over millions of years, Cerro de la Silla has been subject to erosion and weathering processes. These processes have gradually shaped the mountain’s surface, creating the distinct peaks and valleys seen today. Erosion has also played a role in exposing the underlying rock layers.