Here's what John Muir has to say about the San Gabriels in Steep
Trails. He describes the San Gabriels as the most "rigidly inaccessible",
and "ruggedly thornily savage". He describes Eaton Canyon as "the Yosemite of
San Gabriel". And he had choice comments about everybody's favorite chaparral:
"from first to last... I had to contend with the richest, most self-possessed
and uncompromising chaparral I have ever enjoyed". (Ah, what an excellent
turn of phrase! Self-possessed!)
The San Gabriels form the northern wall of Los Angeles. They are partly responsible for LA's famous smog problem. They are pinched between the San Gabriel fault on the south and the San Andreas fault on the north. I've heard that they are one of the fastest-growing mountain ranges in the world. I've been told that one of the 1990's quakes lifted the entire range by a few inches -- in the space of a few seconds this entire mountain range grew by a few inches!! (I've tried to verify these stats, but I'm coming up dry in web searches. Would anyone like to correct me and give me accurate sources?) They top out in the eastern reaches at Mt. Baldy, which is slightly over 10000 feet. Since the LA basin at their feet is only several hundred feet above sea-level, this means they present a truly formidable southern face.
From LA this precipitous southern slope looks relatively featureless -- just steep hills uniformly and monotonously covered in hot dry scrub -- at least when they aren't handsomely capped in sparkling white snow. What most of the millions of people in LA don't know is that hidden in the canyons are verdant woodlands, year-round creeks, graceful waterfalls, sparkling swimming holes, grassy hillsides that periodically burst out in riotous wildflower displays, and rugged cliffs and gorges carved into the solid bedrock (all schists and granites, I think). Higher up on the airy crest you can find open sub-alpine fir and spruce forests, that usually stay snow bound most of the winter. Throughout the mountains you can find huge numbers of deer and the usual rodents/rabbits, as well as bobcat, mountain lion, bighorn sheep, and black bear.
These mountains are the best kept secret in LA. I have repeatedly wandered a few miles into them in the middle of the week and not encountered a single soul -- while literally only a few miles away as the crow flies there are millions of people. For example, climb up and around the lower falls in Eaton Canyon (an easy but airy 3rd class scramble just a mile in from the trailhead), and you'll rarely meet anyone on any time of the week. (Alas, gangs have now discovered this, my favorite retreat. Looks like I'll have to find a new one.) Drive up the Angeles Crest an hour and you'll feel like you're in the middle of nowhere. (Beware motorcyclists though -- they really seem to love racing along this twisty highway.)
I have two main favorite hiking areas. The first is the front range around
Mt. Wilson and Brown Mountain. The second is the high sub-alpine ridges from
about Mt. Waterman to Baden-Powell. I highly recommend John Robinson's
"Trails of the Angeles" guide -- it's generally considered the authority on all
the maintained trails in the area.
Mt. Wilson: There are probably a dozen places just like the front slope of Mt. Wilson, it just happens that it is exceptionally convenient for anyone living in Pasadena or Altadena. There are large number of nice short morning hikes you can take before work: (listed from west to east) Arroyo Seco, Millard Canyon, Sunset Ridge, Mt. Lowe, Eaton Falls, Henniger Flats, Bailey Canyon, up to First Water on the Sierra Madre Trail, and Winter Creek and Sturtevant Falls at Chantry Flats. The shady canyons of Arroyo Seco, Millard, Eaton, Sierra Madre, Santa Anita, West Fork San Gabriel (far side of Mt. Wilson), and Bear Canyon (far side of Brown Mountain) have beautiful pleasant year-round creeks that make great hikes even in the heat of August. My favorite stretch of trail in the area is probably the Rim Trail heading east from the top of Mt. Wilson: fantastic views, gorgeous conifer forests, and surprisingly low traffic. Although Bear Canyon and San Gabriel Peak are close runners-up. If you want a serious challenge comparable to the Grand Canyon rim-to-rim-to-rim hike try my Mt. Wilson Grand Loop.
High Ridges: Most people don't know about this high sub-alpine region of the remote eastern San Gabriels. Those who have done the Pacific Crest Trail through the area will have traversed some of the best the mountains have to offer. People familiar with the lower elevations know just how impenetrable the omnipresent chaparral is, to the point where off-trail travel is virtually unthinkable. Above about 6000 feet it is a completely different story. This airy desert conifer zone makes for extremely pleasant wandering. There are trails to most of the peaks: Waterman, Twin Peaks, Williamson, Islip, Throop, Baden-Powell, etc. But there are a number of side-peaks and ridges off the beaten track that are trailless and wild. I highly recommend the stretch of the PCT from Windy Gap to Baden-Powell. Parts of the Angeles Crest close during the winter, making for fantastic snow-shoeing. Try it in the middle of a snow-storm! There are few mountains safe enough for people like me to enjoy with no winter experience. (Hint: a good alternate approach to the area during the winter is the old highway 39 to Crystal Lake north of Azusa.)
Devil's Punchbowl: I think this is an under-appreciated destination. There are one or two loop trails that will give you a good taste of the area, but if you really want to appreciate it you gotta go scrambling around off-trail. These huge other-worldly slanted sandstone slabs provide a rock-scrambler's paradise. I love wandering up and down the little creek in particular. Note: please try to tread lightly off-trail, staying to rock or washes wherever possible. While it is probably possible to damage yourself in a fall, for the most part the rock is so low-angle that a fall would mostly result in a thrilling shin-scraping slide, not broken bones and death. (Just watch out for vigilant yuccas at the bottom!)
The San Gabriels have countless excellent paved and unpaved roads that are
perfect for cycling. Most have little or no traffic, and even the few that are
busy (like the Angeles Crest - Angeles Forest link to Palmdale) are deserted if
you go at the correct times. Most are pretty strenuous, some are downright
evil. If you train here, the rest of the world will be a cake-walk! Here are
just a few of my favorite rides:
The Angeles Crest Highway: This is a fantastic, challenging ride. There is a popular yearly ride called the "Angeles Crest Century" that starts at JPL, goes up the Angeles Crest all the way to Dawson Saddle (the high point on the highway), then back, detouring around to upper Big Tujunga Canyon on the way there. I believe it totals about 10000 feet elevation gain in 100 miles. The first "hill" up to a little over 3000 feet is a very popular training ride. The next big milestone a little farther along is Red Box Gap at around 4000 feet, where many people veer off to climb another 1000 feet to Mt. Wilson -- a beautiful and very popular destination. If you venture any farther up the Angeles Crest you'll leave civilization completely behind. The next stretch is relatively gentle up and down, but it eventually starts to climb in fits and starts to 6000 at Three Points, 7000 at Cloudburst Summit and Windy Gap, then finally 8000 at Dawson Saddle. Beyond Dawson you get a wonderful descent to the foot of Baden-Powell, another short climb over the Blue Ridge Crest, then a final glorious long descent to Wrightwood, about 70-80 miles from the start in La Canada.
Old Highway 39: This is perhaps one of the hardest rides I've ever done. Follow highway 39 north of Azusa into the heart of the mountains. You get a long gentle stretch pretty early on as you skirt the reservoirs along the lower San Gabriel River, but then it starts climbing and doesn't let up until you finally reach the Angeles Crest at Windy Gap some 5000 feet later. This is also a great ride because there is very little traffic past the reservoirs. The problem is the road is now closed to cars a little past Crystal Lake -- no problem for bicyclists, though.
Old Mt. Wilson Toll Road: This can be done on a road bike, but most sane people would recommend a mountain bike. It is a long unrelenting steep climb from Eaton Canyon to the top of beautiful Mt. Wilson. It steadily climbs almost 5000 feet in a little over 10 miles -- that's an average 10% grade. The views are fantastic, but there's no shade or water most of the way. There is water at the top, however, and it is cool and pleasantly forested in pine and bigcone Doug Fir. This is a popular place for hang-gliders to launch and fly back and forth over the front range taking advantage of the reliable ridge lift.
These mountains tend to be pretty crumbly -- too many darned earthquakes!
But there are several popular places to climb. There is fantastic bouldering
at Horse Flats (off the Sulphur Springs Road near Chilao). It's got super
aretes, thin face, overhangs, etc. on quality rough granite. There's a nice
atmosphere here, high on Mt. Hillyer, with nice views and pleasant open pine
forest. There's also a small top-roping area a little way off from the main
bouldering areas. Check out my friend Chris's cool Horse Flats Photo
Gallery.
The two best sport-climbing areas are Williamson Rock and the Devil's Punchbowl. Williamson seems to be the place for sport-climbing nowadays, it's got quite a large selection of routes of all grades, mostly vertical crimpy stuff on granite/gneiss. The Punchbowl is cool conglomerate sandstone with tons of pockets, but there were access issues last I heard (which was a very long time ago). It was never as popular as Williamson.
I don't know of any long trad routes in these mountains. Maybe Pacifico has some short cracks? You're far better off heading for Joshua Tree or Tahquitz / Suicide near Mt. San Jacinto.
There are countless excellent canyons in the San Gabriel Mountains. The
mountains are so steep that most washes large and small have narrow gorges and
falls at least somewhere along their length. Look at Chris Brennen's Canyoneering in the San
Gabriels for a rather thorough survey of routes both easy and epic. Here
are some of my personal favorites:
Eaton Canyon: This is definitely my favorite place in the San Gabriels. It is a deep rugged gorge cut through the solid granite bedrock of Mt. Wilson. In its shady depths it is luxuriously lined with alders and wildflowers, and strung with countless pools, slides, falls and slot canyons. It is particularly impressive during late spring flood. Later in the summer it is a fine way to escape the heat.
East Fork San Gabriel River: This long canyon is completely non-technical, but it must be done at low water. The high-points are the Narrows and the Bridge to Nowhere, but for me the biggest selling point is its wildness and remoteness. It arises on the slopes of Baden-Powell and Baldy, but the Narrows cut between Iron Mountain and Rattlesnake Peak -- probably the two most difficult summits to climb in all the San Gabriels. Iron Mountain towers something like 6000 feet over the canyon bottom -- an elevation change that takes place over about two miles!
Great Falls of the Fox: Check out Brennen's description of this route -- I can't wait to rope some sucker into doing this with me! I don't know anything about this remote little-visited area northwest of the Tujunga Canyon narrows on the south slopes of Mt. Gleason. The numerous rappels and bushwhacking promise to make this trip quite an adventure.
Devil's Canyon: This is only vaguely technical, but its wildness and mountain lion potential highly recommend it. It cuts through the heart of the San Gabriels from Waterman to the reservoir on the West Fork San Gabriel River.