The Mugu Peak to La Jolla Valley Loop is one of the more challenging trail runs I’ve done before. The first mile climbs 1200 feet, but once you make it past that, the La Jolla Valley Section seems much more manageable. Seriously why is everything named La Jolla so challenging?
About the Mugu Peak to La Jolla Valley Loop:
The Mugu Peak to La Jolla Valley Loop is 9.2 miles long with just over 2000 feet of elevation gain. Over half of that elevation gain comes within the first mile. Parts of the La Jolla Valley loop were overgrown with mustard flowers.
My Experience with the Mugu Peak to La Jolla Valley Loop:
Run: 9.15 miles
Elevation: 2100
Pace: 14:25
Gear Used:
Hammer Nutrition Endurolytes Fizz
I started around 7:45 am. I planned to get to the Mugu Peak to La Jolla Valley Loop earlier, but time got away from me. Luckily it was only about 55 when I started and 60 when I finished. When I got to the trailhead around 7:45, plenty of cars were parked, but spaces were still available. I would say in the 15 car lot, there were still at least five spaces available.
As mentioned, the Mugu Peak to La Jolla Valley Loop starts about as challenging as possible. The trailhead is directly off Highway 1. You follow the Chumash Trail up the side of the mountain. By .7, you’ve already gained 900 feet, and by 1 mile, you’ve gained 1200 feet. It’s imperative to get good shoes as there is plenty of loose rock. It took me about 30 minutes to finish the first mile, and I was pushing it.

At .7, you’ll reach the juncture with the Mugu Peak trail, and you’ll want to keep climbing up. This is definitely the steepest section, and while it’s “only .3”, it will probably take you a good ten minutes, if not more. At parts, I thought it was faster to crawl up.
At the top of Mugu Peak, you’ll see a flag and cross. You get a 360 view of the ocean and Mugu State Park, La Jolla Peak, and even NAS Point Mugu. There is so much to see. The best view of the entire run is here, so if you are looking to cut it short, it’s even worth your while to head back. Not that I didn’t love the La Jolla Valley Loop, but the best part was at the top of Mugu Peak.
You’ll head down and drop quite a bit of elevation (around 700 feet). These miles are fairly easy with primarily smooth single-track trail as you look out along the Pacific Ocean. You’ll come by this later.
You’ll turn right and follow the La Jolla Valley Loop Trail into the grasslands. I was surprised that a lot of the La Jolla Valley Loop was overgrown. I would have expected more people to have been there. I ran through a bunch of mustards plants. I’m not sure if it was a combination. It was like a sea of yellow and reminded me of Northern California. Mustard flowers typically bloom in late April or early May, so we hit it right. They weren’t the only wildflowers, and there were plenty of flowers blooming.
Eventually, you’ll meet back up and head the same way you came. Luckily, you aren’t climbing back up to Mugu Peak, but relatively close. You’ll run the single-track trails along the side until you reach the Chumash Trail, heading back down. Going back to the Chumash Trail might have been the most challenging part. In fact, technical downhill is my least favorite type of running!
You can see more trail runs and hike here.
Love running? You can subscribe to my weekly newsletter or read more about running shoes in my ebook.
Questions for you:
Have you ever run the Mugu Peak to La Jolla Valley Loop?
Have you seen Mustard Flowers before?