Mount Sizer Loop at Henry Coe State Park
Henry Coe State Park is the largest state park in Northern California with an extensive trail system that winds up and down various canyons and over the relatively unknown Blue Ridge section of the Diablo Range. The Mount Sizer loop is 15.3 miles long and has an elevation gain of 4225 ft, which makes it ideal for training for Mount Whitney.
Although Mount Whitney’s elevation is much higher (14,508 feet- the tallest peak in the contiguous US!) it is 22 miles long with an elevation gain of 6100 feet. The Mount Sizer loop has a nearly identical ratio of distance to elevation change making it a great way to see how you might fare during the longer hike.
Best Time to Hike Mount Sizer
The Mount Sizer Loop is best done in the winter or early spring. Chances are if you choose one of these seasons, the grass will be bright green and you’ll see lots of wild flowers blooming.
I went in late May 2016, which was an exceptionally hot and dry spring. I carried 3 liters of water because I didn’t think that the lakes and creeks would have enough, but during better conditions you can filter and utilize various bodies of water on the trail.
Tree coverage is not terribly dense; there are sections of exposed hiking, and parts of the hike go through the remnants of a wildfire. Don’t let this deter you! The section of the trail that was charred provides a surreal backdrop during your descent, the opportunity to see how resilient trees can be, and watch new life begin to grow.
About the Mount Sizer Hike
While hiking you get the chance to descend into deep canyons lined with chamise and other chaparral plants. Throughout the trail you see lots of Grey Pine trees, California Buckeyes, and a variety of Manzanita trees, which are super unique due to their smooth, waxy trunks and sometimes very distinct red or light brown coloring. For budding plant enthusiasts, (pun intended!) Henry Coe has remained insulated from many invasive and non-native plant species, so you get to experience a mostly undisturbed terrain. I saw an acorn woodpecker and trees lined with holes for their acorns. In the fall, it is Tarantula mating season! I’m not a fan of spiders, but it is pretty cool to see these non-poisonous critters scampering around. If you return to Henry Coe for a backpacking trip, beware of Mountain Lions!
There are two ways to approach Mount Sizer; I went up the route that goes over the Hobbs fire road, also known as “The Shortcut”. This nickname is not because it takes significant length off the trail, but because it is the shortest approach to the top. In roughly 1.5 miles you gain 1500 feet at a 22% grade, which is just a fancy way of saying this section is STEEP.
Detailed Trail Guide
From the park headquarters, you begin the trek going from Monument Trail to Hobbs Road. This is not a gradual start, less than a mile in you have already ascended 400 feet! Continue straight until you see the sign for Hobbs road on the left. The trail begins a downward slope from here.
Continue past the Frog Lake turn off, going towards the Middle Fork Coyote Creek crossing. It was not flowing while I was there, but it still looks like an easy creek crossing. Near the water, the trail and surrounding area is lush and green, which is drastically different from the next section. After the creek, brace yourself for The Shortcut!
You immediately start heading uphill, and the salvage of some shade isn’t until you reach the top. My hiking partner thought it would be fun to time this section and see how quickly we could do it. They heard about a rumor that you should be able to finish this section in fewer minutes than your current age. I was confident that I’d be slow moving, so my goal was to finish the section without stopping. I am proud to say that I made it up in fewer minutes than my age ** and I made it the whole way without pausing. (** I barely made it up in the time, I was 25 during the hike and I made it up in 24 minutes.) At the top there is the most perfect bench inviting you to sit, rehydrate, and snack.
From here, follow the Blue Ridge Road and feel free to do the short turn off to the actual summit of Mount Sizer, it’s not as impressive as the ascent, but still worth seeing.
Continue along Blue Ridge Road to the Jackass Trail. This is where you can see evidence of fire damage. Amongst the regrowth of wildflowers and brush was plenty of poison oak. I wore long sleeved shirts and pants for this reason, but the poison oak was super easy to avoid.
The Jackass Trail leads to Poverty Flat Road. The grass was relatively tall, but fairly manageable, and the trail itself is still pretty evident. Poverty Flat road is clearly a misnomer because the trail is not at all flat, it’s about half the grade as The Shortcut, and so it’s pretty intense.
After this climb, you get to the Manzanita Point Road junction. From here you have options as to how to get to the Corral Trail that leads back to the parking lot, either the Forest Trail or the Spring Trail. I went with the Spring Trail because it had shade and was a more clearly defined footpath. The Forest Trail has a self-guided option to look at various different markers, but it adds length to the hike. From the Spring Trail you meander along to the Corral Trail, which quickly opens up to the parking lot.
The Trailhead
The trail starts at the Coe Ranch headquarters by the East Dunne Ave entrance. The trailhead is well marked, but I highly recommend bringing a map.
The Route
From the park headquarters, you begin the trek going from Monument Trail to Hobbs Road.
Continue past the Frog Lake turn off, going towards the Middle Fork Coyote Creek crossing. After the creek, brace yourself for The Shortcut! Immediately start heading uphill, and the salvage of some shade isn’t until you reach the top.
From here, follow the Blue Ridge Road and feel free to do the short turn off to the actual summit of Mount Sizer. Continue along Blue Ridge Road to the Jackass Trail.
The Jackass Trail leads to Poverty Flat Road. After climbing Poverty Flat, reach the Manzanita Point Road junction. From here you can take either the Forest Trail or the Spring Trail to the Corral Trail that leads back to the parking lot. Both trails are narrow single track trails. The Spring Trail is a bit shorter, and the Forest Trail has a self-guided option to look at various different markers.
Depending on the path you choose, meander along to the Corral Trail, which quickly opens up to the parking lot.
Other Details
- Parking- The lot is small, I recommend starting early
- Fees- Park entry fee of $8.00
- Permits- No permit needed for the day hike, but you will need permits if you do an overnight backpacking trip
- Restrooms- Flush toilets below and around the backside of the park HQ are available
- Packing list- Bring plenty of water, sunscreen, hiking poles, and TechNu for poison oak
Trail Safety
Like all outdoor pursuits, hiking can be dangerous. It is up to you to assess your fitness level and education yourself about any potential dangers. While I try to regularly update these hiking guides, you should always research trail conditions before heading out.
Being prepared means arriving at the trailhead with water and some basic provisions. Each and every time I hit the trail I bring a backpack with more water than I think I need, a small first aid kit, and a snack. I also share my itinerary and plans with friends or family and I carry an InReach so I can summon help if needed. If you want to know what I carry in my pack during day hikes check out my blog post about essential gear for day hikers.
Stay safe, enjoy the trail, and soak up the magic of nature!
