Overview: The Sierra Gorda isn't one world, but a patchwork of distinct landscapes separated only by mountainous elevation. From mist-covered cloud forests on the east side to a rain-deprived desert on the west, the Sierra Gorda is comprised of towering cacti, a crystalline river inhabited by the unique axolotl, and a 1,400-foot monolith that stands as a tribute to the region's volcanic past. Higher up, tropical and alpine species of fauna and flora intermingle, creating the signature diversity unique to the "wild heart of central Mexico."