"THE BACKBONE OF LUZON"
Sierra Madre, mountain system of Mexico. It consists of the Sierra Madre Occidental (to the west), the Sierra Madre Oriental (to the east), and the Sierra Madre del Sur (to the south). These ranges enclose the great central Mexican Plateau, which itself is a part of the system—although the northern portion of the plateau also is considered to be part of the Basin and Range Province in the United States—and is broken by blocks of mountain ranges and large ephemeral drainage basins called bolsones (“pockets”).
Sierra Madre is the longest mountain range in the Philippines, fondly called the “Backbone of Luzon”. It spans almost 700 kilometers in length with its highest peak standing at an elevation of 1,266 meters above sea level (for a more concise comparison, that’s approximately three times the height of Petronas Tower).