Temblor Range

San Andreas Fault runs through Carrizo Plain at the foot of the flower-filled Temblor Range

5.5 miles round trip, 1400 feet elevation gain (variable length and elevation gain)
Difficulty: Moderate-strenuous; off-trail experience and route-finding skills necessary

Access: Rough dirt road to access this range (high-clearance recommended), no entrance fee

The trailless wilds of California's Temblor Range in Carrizo Plain National Monument, hidden in the Coast Range between the Bay Area and Los Angeles, explode with some of the densest and most spectacular wildflower blooms on the continent after rainy winters. Although no trails lead to any of the peaks of the range, the treeless Temblor Range beckons to be explored during these superblooms, promising mountain slopes overflowing with daisies and phacelia as well as sweeping views over the isolated grassland, home to pronghorn and kit foxes, that's been nicknamed "California's Serengeti." Running through the heart of this plain is the source of those temblors, the mighty San Andreas Fault, which is more physically apparent on this arid plain than anywhere else. If you've seen photos of aerial views of the San Andreas Fault rupturing through a desert, then you've seen photos of the Carrizo Plain.

Despite being part way between the two largest metropolises of the West Coast and just over an hour off I-5, Carrizo Plain National Monument is one of the least known and visited federally preserved parks in the state of California. Established during the Clinton Era under the Antiquities Act and overseen by the Bureau of Land Management, this national monument preserves a dry grassland- at 5 inches of annual precipitation, a desert, really- sandwiched between the Caliente and Temblor Ranges. Despite being just miles from San Luis Obispo and the ocean, rainfall in the Carrizo Plain never reaches the sea, instead flowing into the endorheic Soda Lake at the heart of the plain. This great grassland today is a last refuge for many species which in the past wandered the Central Valley and other parts of coastal Central California; this is the only land wild and big enough for them to call home now.

I first came to know about Carrizo Plain by happy accident: during a flight from Tokyo to Los Angeles, I looked down from my window seat and saw the great San Andreas Fault cutting through the heart of a flat desert valley. I had enjoyed studying geology as a kid and immediately recognized this as the iconic view of the fault found in textbooks- perhaps the most recognizable view of an earthquake fault in the world. Checking my map of the state of California later, I found that I had been looking at the Carrizo Plain; I thought about visiting constantly until six years later, during a superbloom, I finally made it a reality.

The San Andreas Fault cuts through Carrizo Plain

Short of viewing the San Andreas Fault from the air, the high ridges of the Temblor Range in the southeastern part of Carrizo Plain National Monument is the only place wher you can really see the fault's unique ruptured, straight-line appearance; the fault runs closer to the eastern side of the plain, making it more easily visible from the Temblor Range than from the Caliente Range on the other side of the valley. The rupture is more pronounced near the southern end of the plain than at the northern end, where the fault is noticeable at Wallace Creek but doesn't look quite as dramatic as it does by Traver Ranch. Hiking in the southern part of the Temblor Range also has less red tape: along the northern part of Elkhorn Road, private land is intermixed with public land while the southern Temblors west of the ridge crest is entirely public.

If you choose to explore the Temblor Range, there will be no trails to guide you: you'll simply have to make your way cross-country up the ridges of the range from Elkhorn Road. The Temblor Range is a relatively easy place to do this, as the lack of tree coverage makes way-finding fairly easy and the terrain is relatively easy to hike on without major obstacles, but it's important to know that this is still off-trail hiking and requires some ability to read terrain and navigate. The best way to choose a place to hike, if you're focused on the superbloom, is to simply drive along Elkhorn Road and then hike into the range when you see denser and more copious patches of flower blooms on the ridges above. If you'd like to catch the best views of the San Andreas Fault, I recommend hiking the Temblor Range south of Crocker Spring Road. I started my own hike from at 35.117 N, 119.622 W, but you can probably find equally if not more enjoyable hikes elsewhere in the range. The crest of the Temblor Range runs between about 3200 and 3500 feet while Elkhorn Road generally floats around 2400 feet above sea level, so most hikes to the crest of the Temblors will put require about 1000 feet of elevation gain or more if you follow the many bumps along the side ridges. Generally, Elkhorn Road is about 2 to 4 miles distant from the Temblor Range crest, although following nonlinear ridges will obviously add to that distance. It is a good range for off-trail day hikes.

There are no paved roads in Carrizo Plain National Monument. Many of the roads in the plain can become impassable after rainstorms and the roads cutting through the heart of the plain- Simmler and Panorama Roads- are often closed through the winter and spring when the endorheic basin around Soda Lake is full. Access to the Temblor Range requires driving the Elkhorn Road, which can be accessed either from California Highway 58 in the north via Seven Mile Road or from California Highway 166 from the south from the Elkhorn Grade Road. The Elkhorn Road is quite rough in spots and while it may be passable by passenger cars at times, it is far safer to come out here with a 4WD high clearance vehicle.

Elkhorn Road is itself a tremendously scenic drive, especially at its southern end. Elkhorn Valley, a portion of the Carrizo Plain sandwiched between the Temblor Range and hills along the San Andreas Fault, has an isolated and otherworldly feel. The barren look of the Temblor Range hills contrasting with the lush valley and the colorful fields of phacelia and daisies is extremely striking.

Phacelia fields on Elkhorn Road

Multi-color blooms along Elkhorn Road

I started my hike slightly farther north, at 35.117 N, 119.622 W, when I spotted nice wildflower color along the crest of the Temblors. I set my sights on the crest of the ridge from here and set out across the grassland. Carrizo Plain is best known for its tri-color blooms of orange fiddleneck, yellow daisies, and purple phacelia (desert candle and owl's clover are two other commonly spotted flowers here). During superbloom years, the peak bloom often comes in early April; my mid-March visit was slightly on the early side and I primarily saw daisy blooms higher up in the Temblor Range, although there were some patches of phacelia on the plain itself and I found one small area where all three colors were mixing at the start of my ascent. Desert USA compiles useful reports that cover bloom status each year.

Multi-color blooms before the ascent

I picked a ridge and simply followed it up to the crest of the Temblors. While there were no formal trails here, there are many faint paths established by the kangaroo rats that lived on the range's slopes, so I followed those at times while I ascended through slopes of agave, grass, and loose rock.

Agave on the slopes of the Temblor Range

Soon, I arrived at some profusely daisy-coated slopes: the density of the blooms here was astonishing. One bump in the ridge led to the next and I enjoyed ascending through these marvelously flower-coated mountainsides. As I made my way uphill, sweeping views opened up of the steep ravines on either side of the ridge, the other flower-covered ridges and peaks of the Temblor Range, the Caliente Range across the valley, and the remarkable rupture of the San Andreas Fault running through the heart of the Carrizo Plain.

Daisy-coated slopes of the Temblors

View of the San Andreas Fault running through Carrizo Plain

Daisy-coated ridges of the Temblor Range

Temblor Range and daisies

The San Andreas Fault is perhaps the best known example of California's active geology. Here, the Pacific Plate comes in contact with the North American Plate. Although the North American plate is pushing west here, the junction between these tectonic plates is a transform boundary- one where the two plates slide past each other, rather than colliding. This boundary is expressed through a large number of faults at the Earth's crust and the San Andreas Fault, a strike-slip fault, is the largest rupture line along which these plates can slide. Movement along this fault has torn apart volcanic rock from the ancient Neenach Volcano, part of which forms Pinnacles National Park near Salinas and the other part of which is nearly 200 miles away just north of Los Angeles. On the Carrizo Plain, the San Andreas Fault has caused lateral shifts in the washes of streams that drain the Temblor Range.

Daisies and the San Andreas Fault

Once I made it to the crest of the Temblor Range, a fence on the east delineated the border of the national monument. Looking east, I had a view down the flower-coated east slopes of the Temblor Range down into the Central Valley. Below the Temblor Range, near the town of Taft, was the Midway-Sunset Oil Field, the largest oil field in California and part of a vast collection of oil fields at the southern end of the Central Valley near Bakersfield. Kern County- which encompasses most of these oil fields- is the most productive oil producing county in the United States at the time of writing. The abundant oil resources in the area have been subject to recent political contention, as the Bureau of Land Management moved to allow one drilling lease within the monument in the Caliente Range in May 2020.

View east towards oil fields around Taft

San Andreas Fault running across Carrizo Plain

I enjoyed the views at the summit along with the copious flower fields. As this was an off-trail adventure, I had the spot entirely to myself. You'll almost certainly encounter similar solitude if you hike in the Temblor Range. It was difficult to believe that I could enjoy such extraordinary wildflower displays and the awesome view of the San Andreas Fault alone, especially as this area is not that difficult to access from California's major cities. I watched the sun set over this magical plain when I got back to the truck and was glad I had found a way atop the Temblor Range to appreciate this magnificent landscape.

Sunset on Carrizo Plain