The direct out and back trail run from the Victory Trailhead at Ahmanson Ranch through East Las Virgenes Canyon to the Upper Las Virgenes Canyon Trailhead is about 3 miles each way.
This variation bypasses most of East Las Virgenes Canyon. It climbs up to Lasky Mesa and then descends “The Beast” to East Las Virgenes Canyon about 0.4 mile before it joins the fire road in Upper Las Virgenes Canyon. This fire road can be followed south to the Upper Las Virgenes Canyon Trailhead, the turnaround point.
Depending on the exact route, the trail run totals about 7.5 miles, with about 825 feet of cumulative elevation gain. The Beast is the longest continuous hill and is about 0.8 mile in length.
When it rains a lot, sections of East Las Virgenes Canyon can get really muddy. This route avoids the worst of the gooey, stick-on-your-shoes mud.
Update January 17, 2023. With the additional rainfall this January the “best” route up to Lasky Mesa is on the dirt road. The single track is wet and muddy in spots. The lower half of the Beast is eroded and somewhat muddy. I have a pair of shoes that I use in the muck and wet. They haven’t dried out for weeks.
Originally published June 28, 2008. Updated December 30. 2022.
Without a doubt, the Chumash Trail is one of my favorite short “after work” trail runs. Popular among hikers, mountain bikers, and runners, the Chumash Trail starts on Flanagan Drive in eastern Simi Valley and ascends the convoluted western flank of Rocky Peak Park to Rocky Peak Fire Road. It’s single-track trail all the way, gaining about 1175′ over 2.7 miles.
From a trail runner’s training perspective, it is a nearly ideal short, technical, higher heart rate workout. It has a few tough sections but is generally very runnable. When I’m chugging up the trail, it seems just about the time my heart rate is going to go lactic, the trail will back off or contour. Because I usually run the trail near my aerobic maximum, it’s a great indicator of where I am in my training. Over-training, or any other fitness issue, is usually plainly — and sometimes painfully — evident.
In many ways running down the Chumash Trail is more difficult than running up. It can be very challenging to run down a rocky, technical section of trail with any speed. Running a trail like the Chumash Trail can help develop the skill and strength necessary to do downhills with better technique and more speed.
I don’t think I’ve ever run this trail fresh, but a couple of times a year, when my legs feel good, it’s fun to really push the Chumash Trail up and down. Like most running, there’s a balance — push too hard on the up and there won’t be enough left to push the down.
Here is an interactive, 3D terrain view of the Chumash Trail Out & Back to Rocky Peak Road. The map can be zoomed, tilted, rotated, and panned using the navigation control on the right. Track and placename locations are approximate and subject to errors. Poor weather and other conditions may make this route unsuitable for this activity.
There are several ways to extend the basic out and back. One option is to turn left on Rocky Peak Road and run a mile to “Fossil Point.” Another is to turn right and run 1.6 mile to the Rock Peak overlook.
I saw a flash of brown through the bushes on the trail ahead. I stopped as a deer emerged from a switchback. The doe was walking slowly up the trail with her mule-like ears turned back toward me. I said something like, “Where are you going?”
She turned toward me and stared quizzically. As I slowly pulled the phone from my pack, I continued to talk. Her expression was a mix of caution and curiosity. It was as if she couldn’t quite make up her mind what I was about.
Mule deer at Trippet Ranch
This was peculiar behavior for a deer in this area. It wouldn’t be so strange if I was at Trippet Ranch. The deer there graze around the oaks and grasslands near the parking lot and are used to seeing people. But in decades of running the Chumash Trail, I’ve only occasionally seen deer, and they have always been skittish and quick to react.
This doe watched me as I slowly walked around the bend and toward her. I was reminded of a friend’s experience, when he was hit on the shoulder by a spooked deer. Not wanting to force a reaction, I stopped. The deer casually stepped off the trail and disappeared down the ravine.
Later, running down Las Llajas Canyon, I was startled by the sound of something large moving in the brush. This time I got only a fleeting glimpse, as the deer bounded uphill through the trees, rocks, and brush.
Was that thunder? I warily eyed the dark clouds over the mountains and pondered the situation.
I was about halfway to the top of the Chumash Trail and was planning to run along the crest to Rocky Peak. The run had started in short sleeves and sunshine, but it was pretty obvious that wasn’t going to last.
Chumash Trail about a mile from the trailhead
A cold upper-level low had brought badly needed rain to the area for the past two days. The low was moving off to the east, but there was still a chance of afternoon showers and maybe even a thunderstorm.
It was the “thunderstorm” part that I needed to pay attention to. I had enough gear to deal with a downpour and cooling temps, but electrical storms are no fun at all.
I decided to continue to the top of the Chumash Trail and reassess. As I worked up the trail, I pictured the counterclockwise circulation around the low, and how convective cells develop over the mountains and then dissipate as they drift south. The concern was that the cells don’t always dissipate.
Rocky Peak Road near Rocky Peak
It looked like things weren’t getting any better at the top of the Chumash Trail, but it wasn’t worse either. I hadn’t heard any thunder for a while, and most of the activity seemed to be a few miles to the west and east. Having been starved of stormy weather for much of the rain season, I turned right on Rocky Peak Road and headed south toward Rocky Peak.
The run from the Chumash Trailhead to Rocky Peak is a challenging mix of technical single-track trail and hilly fire road. There are wide-ranging views of Simi Valley & Simi Hills, the San Fernando Valley, Santa Monica Mountains, Ventura County mountains, and San Gabriel Mountains. On a clear day, the view can extend to the Channel Islands, Saddleback, and San Jacinto Peak.
NOAA radar mosaic at the time I was on Rocky Peak
The actual turnaround point for a run to “Rocky Peak” varies. Some like to turnaround at the high point of Rocky Peak Road that is near Rocky Peak. Most of the time, I turnaround at a viewpoint that is at the end of a spur trail that branches off from the high point of Rocky Peak Road. From time to time, it’s fun to hike over to Rocky Peak and scramble to the top. That’s a bit more involved and requires some route-finding.
I felt the first raindrops as I reached the high point on Rocky Peak Road and turned onto the spur trail that leads to the overlook. There was some increased development to the east, but it looked like there would be enough time to get over to Rocky Peak, take a couple of pics, and then head back.
Oat Mountain, shrouded by rain
I felt a little exposed on top of Rocky Peak. I hadn’t heard any thunder for the past hour, but a cell to the east was spouting heavy rain over the San Fernando Valley, which meant there was probably enough development to produce lightning. I took the title photo and a couple of others and hurriedly descended from the peak.
Back on Rock Peak Road, the sprinkles increased, and the showers became more steady as I ran north toward the Chumash Trail. Under the dark clouds, a raven perched on a large pinnacle cawed incessantly, either enjoying the rain or complaining about it. In the distance, a siren wailed down in the valley. It was cold, and I was very glad to have an extra shirt, sleeves, gloves and a light rain shell.
Mix of sun and rain on the Chumash Trail.
As I began the descent of the Chumash Trail, the sun briefly broke through the clouds, reflecting brightly on the wet sandstone rocks. I breathed deeply, relishing the smell of the cleansed air and wet chaparral, and continued down the trail.
Instability associated with an upper low resulted in some pop-up showers and thunderstorms today.
As I ran up the Chumash Trail on the east side of the Simi Valley I kept a close eye on a cell that developed near Ladyface in the Agoura Hills. That cell didn’t track as much to the east as I thought it might, but other cells were developing to the east and south of Rocky Peak and Santa Susana Pass area and at one point I heard the rumble of thunder.
As it worked out, I only had a few sprinkles on the run, but drove home in the rain!
