The San Gorgonio Wilderness

The San Gorgonio Wilderness is the climax region of the San Bernardino Mountains in Southern California. Located on the San Bernardino National Forest approximately 75 miles east of Los Angeles (click here for vicinity map), the Wilderness receives approximately 200,000 visitors per year. Its 58,969 acres harbor two small lakes, meadows, streams, 100 miles of trail, densely forested northern slopes, and rugged terrain. Elevations range from 4,400 feet to 11,499 atop namesake Mt. San Gorgonio. Eleven of twelve peaks in the Wilderness recognized by U.S. Geological Survey maps are over 10,000 feet in height, with Mt. San Gorgonio being the highest. As the highest peak between the Sierra Nevada mountain range and the Mexican border, Mt. San Gorgonio offers unparalleled views of metropolitan Los Angeles and the Mojave Desert. More great information here.



"Flanking the pass along its northern side stands Mount San Bernardino [Mt. San Gorgonio]…the summit piercing through a marbling of perpetual snow up to the height of ten thousand feet". 
Clarence King-Mountaineering in the Sierra Nevada (1871) 

Getting to the Wilderness | Maps & Books | Seasonal Information
Permit System | Adventure Pass | Wilderness Regulations
Flora & Fauna

Getting to the Wilderness
From Highway 10 near Redlands, take Orange Avenue/Downtown (Hwy 38) north to Lugonia. Make a right (east). After approximately eight miles, Mill Creek Ranger Station is reached (just 100 yards after the Yucaipa/Bryant Street cutoff). Continue east on Hwy 38 approximately six miles to Forest Falls for the Momyer and Vivian Creek trailheads (3 miles). For all other trailheads, avoid the Forest Falls cutoff and continue north on Hwy 38 up the mountain. (Click here for a vicinity map of the region).

Maps and Books

Maps and books are available through the Backcountry Store or directly from the Mill Creek Ranger Station in Mentone. Four USGS 7.5 Minute quadrangles cover the Wilderness: San Gorgonio Mountain, Moonridge, Big Bear Lake, and Forest Falls. You can also get the TOPO CD-ROM to customize maps for the Wilderness.

Interactive San Gorgonio Wilderness Map

Trail Mileages/Elevations in the San Gorgonio Wilderness

Trailhead Mileage/Elevation Gain to the Top of San Gorgonio

Seasonal Information

Summer: The San Gorgonio Wilderness during an average year may be snow-free from June through December. Brief thunder and lightning showers are a common occurrence during the afternoon generally in the months of July and August. Average summer temperatures are 75 F to 80 F degree highs, with nighttime lows of upper 40's and lower 50's (Fahrenheit).

Winter: The San Gorgonio Wilderness generally receives it's first snows in late December - during drier years not until mid to late January. Snowpack can and may exceed ten feet in some areas during the winter and spring. Daytime winter highs are approximately 30's to 40's, with nighttime lows around 0-20 degrees Fahrenheit (dependent upon elevation and localized weather occurrences).

The San Gorgonio Wilderness offers unparalleled opportunities for solitude during the winter and spring months. Miles of backcountry terrain is available for skilled skiers, offering up to 3500' descents (off the north slope of Mt. San Gorgonio) and moderate cross-country terrain for intermediates.

Snow climbing and mountaineering is a popular winter and spring pursuit for those equipped with ice ax and crampons and suitable skills. climberThe northern aspects of most of the peaks in the Wilderness present easy to   moderately difficult climbs. Avalanche caution must be exercised in the San Gorgonio Wilderness. Always travel prepared, obtain the proper permit, and notify someone at home of your itinerary.

For those interested in climbing and backcountry descent details, we  suggest that you post notices at the San Gorgonio Backcountry Bulletin Board, or at the rec.backcountry or rec.climbing Usenet newsgroups.

During early spring and early summer, less experienced travelers may find difficulty in navigating their way to their intended destination due to lingering snowpack or icy stretches of trail. Therefore, it is important to check the Trail Conditions page or call ahead to the Mill Creek Ranger Station for such details if you are unsure of your abilities. 


Permit System

In April 1973, a fixed quota permit system was enacted for the San Gorgonio Wilderness "to promote, perpetuate, and to restore the wilderness character of San Gorgonio". All visitors are required to secure a permit before entry into the wilderness for both dayhikes and overnight travel. Maximum group size per permit is twelve persons and permits are issued by zone. Permits can be gotten on day of entry, but only a limited  number of permits are held in this reserve. There is no guarantee that you will secure a permit on the day of your planned hike, especially on holiday weekends. Self-issue permits FOR DAYHIKING ONLY (no overnight trips!) are available on the outside of the Mill Creek Ranger Station before it opens each day. Again, there are only a limited number of permits for each trail, and there is no guarantee that the permit you want will still be available. Arrive early, be flexible, and have alternatives in mind should this be the case.

THE SGWA DOES NOT ISSUE PERMITS! If you are planning a trip to the wilderness, please inquire about permits at the Mill Creek Ranger Station, 34701 Mill Creek Road, Mentone, California, 92359. Phone (909)382-2882, or apply for a permit.


National Forest Adventure Pass

What is the National Forest Adventure Pass? It's a recreation pass for visitors using the Angeles, Cleveland, Los Padres, and San Bernardino National Forests. The Adventure PassPass must be displayed on visitors' vehicles and is available in two forms: a daily pass for $5.00 and an annual pass good for one year from the month of purchase for $30.00. All forest visitors are required to display the Pass in their vehicles when parked on the Forest for recreation purposes. You will not need a Pass when you are traveling through the Forest but not stopping. When you are parked at your residence or at an organization camp in its permitted area, or are in an area covered by a special use permit. A Pass is not required for those stopping for information at Ranger stations, visitor centers, and other Forest Service offices, or for off-road (green sticker) vehicles. Volunteers and educational institutions, such as school buses that bring children to the Forest for an outing, are also exempt. Please click here for much more information about the Pass.

Wilderness Use Regulations

In order to promote the primitive character of the San Gorgonio Wilderness, and to ensure a safe and memorable experience for the visitor, the San Gorgonio Wilderness is safe-guarded by important federal regulations. If you are planning a trip to the Wilderness, please click here to familiarize yourself with these regulations. Additionally, to insure that future visitors to the San Gorgonio Wilderness may enjoy the same pristine environment you did, minimum impact ethics must be observed during your visit. Please click here to learn more about minimum impact ethics.

NOTE: On September 8, 1998, ALL CAMPFIRES BECAME INDEFINITELY PROHIBITED WITHIN THE SAN GORGONIO WILDERNESS. Maximum group sizes were also reduced, in addition to further changes. Please read here for details.

Flora and Fauna and Geology

The San Gorgonio Wilderness is home to several distinct biotic communities. These include: chaparral, yellow-pine forest, montane meadows, lodgepole forest, sub-alpine, and alpine fell.

During the Pleistocene period, the Wilderness was home to at least seven cirque and valley glaciers heading at elevations between 10,300 and 11,300 and ranging from mile to 1 miles in length. None descended below 8,700 feet. Today, one can identify the ancient glaciation by obvious cirques and large medial and terminal moraines up to 700 feet in height, one of which formed Dollar Lake.

Common rock types of the Wilderness are:

Muscovite Biotite Gneiss (click for photo)
Location: Grinnell Mountain
Age: Proterozoic (1.76 billion years)
Description: A metamorphic rock with well-developed, planar layering and linear fabric, typical of rocks on the slopes north of Dry Lake, San
Gorgonio Wilderness.

Rock Type:
Muscovite Biotite Migmatitic Gneiss (click for photo)
Location: San Gorgonio Mountain
Age: Uncertain, probably Cretaceous (80 million years)
Description: A metamorphic rock with well-developed, convolute layering, cut by light tan granite dikes, typical of rocks on the north slope of San
Gorgonio Mountain, San Gorgonio Wilderness.

Rock Type:
Muscovite Biotite Granite (click for photo)
Location: San Gorgonio Mountain
Age: Uncertain, probably Cretaceous (80 million years)
Description: An igneous rock without visible layering, typical of rocks
along the summit ridge of San Gorgonio Mountain, San Gorgonio Wilderness.

(photos above courtesy of Andy Barth; Department of Geology, Indiana University. Thank you!)

The Wilderness is also host to numerous species of plants and animals.
The following lists demonstrate species most common to the San Gorgonio Wilderness.


Shrubs | Trees | Wildflowers | Birds | Mammals

All links lead to info/photos regarding the species. Please notify the site administrator if you find invalid links. Click the speaker  to hear the sound of the stated species

Common Name Scientific name Overview Photo Closeup Photo
Chinquapin Castanopsis sempervirens
Manzanita Arctostaphylos spp.
Scrub Oak Quercus dumosa
Bracken Fern Pteridium aquilinum
Willow Salix spp.
Stinging Nettle Urtica spp.
Whitethorn Ceanothus cordulatus
Wild Buckwheat Erigonum spp.
Elderberry Sambucus caerulea
Wax Currant Ribes cereum
Sierra Gooseberry Ribes roezlii
Rabbitbrush Chrysothamnus viscidiflorus
Yucca, Our Lord's Candle Yucca whipplei
Sedges Carex spp.  
Bush Monkeyflower Mimulus aurantiacus
Miner's Lettuce Claytonia perfoliata
Coffeeberry Rhamnus californica  

Common Name Scientific name Overview Photo Closeup Photo
Monkeyflower Mimulus guttatus

Scarlet Monkeyflower Mimulus cardinalis  

Snow Plant Sarcodes sanguinea (saprophyte)
Pine Drops Pterospora andromedea (saprophyte)
Spotted Coral Root Corallorhiza maculata
Orange Peel Aleuria aurantia fungus  
Wild Rose Rosa californica
Lemon Lily Lilium parryi

Hartweg's Iris Iris hartwegii australis  
Western Wallflower (Erysimum capitatum)
Cow Parsnip Heracleum lanatum
Ranger's Button Sphenosciadium capitellatum
Indian Paintbrush Castilleja spp.
Fireweed Epilobium angustifolium
Alpine Shooting Star Dodecatheon alpinum
Cranesbill or Richardson's Geranium Geranium richardsonii
Mountain Heather Phyllodoce breweri
Bigelow's Sneezweed Helenium bigelovii  

Scarlet or Bridge's Penstemon Penstemon bridgesii

Mountain Penstemon Penstemon newberryi


Beardtongue Penstemon Penstemon grinnellii

California Fuschia Zauschneria californica
Crimson Columbine Aquilegia formosa

California blue-eyed grass Sisyrinchium bellum  

Dwarf Lousewort Pedicularis semibarbata
Lupine Lupinus spp.
Douglas's Iris Iris douglasiana
White Phlox Phlox diffusa
Mountain Sorrel Oxyria digyna
California Corn Lily Veratrum californicum
Yarrow Achillea lanulosa
Wheeler's cinquefoil Potentilla wheeleri
Blazing Star Mentzelia laevicaulis  
California Indian Pink Silene californica  
Leafy Mistletoe Phoradendron tomentosum  
Purple Nightshade Solanum xanti  

Common Name Scientific name
Black Oak Quercus kelloggi
Mountain Mahogany Cercocarpus ledifolius
Coulter Pine Pinus coulteri
White Fir Abies concolor
Limber Pine Pinus flexilis
Lodgepole Pine Pinus contorta
Jeffrey Pine Pinus jeffreyi
Ponderosa Pine Pinus ponderosa
Incense Cedar Calocedrus decurrens
Sugar Pine Pinus lambertiana
Black Cottonwood Populus trichocarpa
Quaking Aspen Populus tremuloides


Common Name Scientific name song Photo
Violet-green Swallow Tachycineta thalassina    
White-throated Swift Aeronautes saxatalis
Steller's Jay Cyanocitta stelleri speaker
Clark's Nutcracker Nucifraga columbiana speaker
Common Raven Corvus corax speaker
Mountain Chickadee Parus gambeli speaker
Black-capped Chickadee Parus atricapillus speaker
Cassin's Finch Carpodacus cassinii speaker
Song Sparrow Melospiza melodia speaker
White-breasted Nuthatch Sitta carolinensis
American Robin Turdus migratorius speaker
Western Tanager Piranga ludoviciana speaker

Green-tailed Towhee Pipilo chlorurus speaker
Dark-eyed Junco Junco hyemalis
Williamson's Sapsucker Sphyrapicus thyroideus
White-headed Woodpecker Picoides albolavartus speaker
Acorn Woodpecker Melanerpes formicivorous speaker
Red-tailed Hawk Buteo jamaicensis speaker speaker


Cooper's Hawk Accipiter cooperii


Common Name Scientific Name Vocal Photo
Chipmunk Tamias spp.(species unidentified)  
Golden-mantled Ground Squirrel Spermophilus lateralis
Western Gray Squirrel Sciurus griseus
Black Bear Ursus americanus  
Bighorn Sheep Ovis canadensis nelsoni
Mountain Lion Felis concolor speaker

Coyote Canis latrans  
Mule Deer Odocoileus hemionus