The San Francisco Mountains are a mountain range in northern Arizona, United States, located just north of Flagstaff. The highest summit is Humphreys Peak, 3,850 m, situated at . They consist of the remains of a once-higher group of extinct volcanoes.

The biologist Clinton Hart Merriam studied these mountains in 1889, describing a set of six 'life zones' found from the base to the summit of the mountains, based on the major components of their flora:

• Lower Sonoran Zone - Sonoran Desert plants
• Upper Sonoran Zone - Colorado Pinyon and juniper woods
• Transition Zone - Ponderosa Pine forests
• Canadian Zone - Rocky Mountain Douglas-fir and White Fir forest
• Hudsonian Zone - tree-line forests of Rocky Mountains Bristlecone Pine and Engelmann Spruce
• Arctic-Alpine Zone - alpine tundra
  

Merriam considered that these life zones could be extended to cover all the world's vegetation types with the addition of only one more zone, the tropical zone. His pioneering studies remained the one of most widespread climate zone classifications, in use for nearly 80 years.

The peaks were named by Flagstaff, Arizona locals during the 1880's after the (not quite believed) claim that the far off city of San Francisco, California could be seen from the summit of the highest peak.

The mountains have considerable religious significance to local Native American tribes (Navajo, Hopi, and Zuni.) The mountain provides a number of recreational opportunities, including snow skiing and hiking. Hart's Prairie is a well loved hiking area nestled just below the mountain's ski resort.

Sudden and relatively unpredictable weather changes in Fall or Spring have resulted in unexpected snow fall bringing death from exposure to unprepared hikers. Native Americans sometime mention a legend that ghostly Kachina spirits appear during deadly snowfalls on the peaks.

External link

• San Francisco Mountains: USGS factsheet