- Because these peaks tower up to 6,000–10,000 feet above the desert floor, ascending them is ecologically equivalent to traveling from Mexico to Canada
- This rapid change in elevation creates a unique biodiversity hotspot where five distinct biomes—ranging from desert scrub up to sub-alpine coniferous forests—exist on a single mountain massif
-One of the most readily accessible is at the end of the Mount Lemmon Scenic Byway at the top of the Santa Catalina Mountains