On a beautiful November, fall day, I headed into the Santa Cruz Mountains and Castle Rock State Park for what I hoped would be an awesome easy-ish hike. The Big Basin and Castle Rock Loop promised to connect the ecosystems of two of my favorite parks, Big Basin and Castle Rock, and hopefully provide the best of both: big views and redwood forests!
Miles/Elevation:
7.3 miles
1,118 feet vertical gain
About Castle Rock State Park:
Castle Rock State Park is a fantastic state park just outside San Jose California. Located in the Santa Cruz Mountains, it is easily accessible, but contains miles of amazing hikes filled with awesome views of the range. Named for the prominent Castle Rock, a rough rocky outcropping, the park begins on a ridge adjacent to highway 35, and continues down the slope into the heart of the Santa Cruz range.
With 34 miles of hiking trails, Castle Rock State Park has plenty of room to explore. Whether you want an easy day hike or the solitude that comes with an overnight backpacking trip, Castle Rock can provide it! For the more adventurous, Castle Rock is one of the best rock climbing destinations in the South Bay!
Getting To The Trailhead:
The trailhead for this hike is located at the intersection of highways 9 and 35 at the Saratoga Gap Parking area. From San Jose, take highway 9 into and through Saratoga, and once up the climb at the intersection with 35, turn left and immediately pull into the parking lot on the left. There is no public transit to the trailhead, so you will need to drive yourself or get a ride.
The Big Basin and Castle Rock Loop:
Down The Hill:
From the parking lot, cross highway 35 and follow highway 9 downhill towards Big Basin and Boulder Creek for a couple hundred feet. You will quickly encounter a trail that leads left down from the road. Take this trail to start the loop!
This trail that you will find yourself on is the famed Skyline to the Sea Trail, an overnight backpacking route from Castle Rock State Park all the way to the beach north of Santa Cruz! Follow it for a tenth of a mile, then stay left at the fork to continue downhill on the Saratoga Toll Road Trail.
This trail is actually the remnants of an old road that ran from Santa Cruz to the Santa Clara Valley. Now, vehicles obviously use highway 9 nearby, or 17 a bit further away, so this is purely used as a hiking trail.
Always be sure to follow the 7 Leave No Trace Principles when in the outdoors!
The toll road trail heads downhill consistently, but the incline is never severe; it’s a nice, easy, descent. Most of the hike down the hill is through dense forest. You’ll begin in a leafy forest near the start, but you’ll travel through a number of distinct ecosystems as you descend. Leafy forest, pine forest, redwoods, it’s really cool to watch the environment change around you!
Always follow basic trail etiquette when on trail!
Roughly halfway through the descent, you’ll start getting some nice views through the trees of the hills and valleys in the distance. If you’ve ever hiked at some of the more popular trails in Castle Rock before, these views will be familiar, but it’s nice to start getting some bigger views! The panoramas though are brief, so enjoy the big views while you have them!
The biggest negative of the hike down for me was the constant noise. I think I only saw one other person on the descent, so the trail was really quiet which was nice, but there was constant traffic and gun noise. The trail basically parallels highway 9 for the first 3 miles, so you can hear cars most of the time. You can also hear gunshots from the nearby shooting range which is a little distracting and disconcerting!
After just under 3 miles of hiking, you’ll arrive at another intersection. The toll road trail continues straight, and a small trail takes a hard left. Take this hard left, and continue along the Travertine Springs Trail.
The Travertine Springs Trail:
The Travertine Springs Trail takes you into the lowest reaches of this loop. The foliage here is primarily dense pine forest with a lot of dense brush along the forest floor. I’ve read that bugs can get really bad through here, but when I did this hike in November, I didn’t encounter any. The reason for the potential bugs is the water!
Water is pretty rare in this part of the world, so you don’t often see wetlands around! The name of the trail sort of gives it away, but you will be hiking past some springs with sitting water near the trail. It’s a bit of a strange sight seeing all the rich, green vegetation around, especially during a California fall, but it’s a cool place to walk through!
Check out nearby Bear Creek Redwoods too!
The highlight of the entire hike for me came shortly after the springs. Perhaps half a mile after the springs, you will cross the infant San Lorenzo River. At this stage it is a mere creek, but the setting of this crossing is beautiful! The river gently pours through the valley, beneath towering pines and redwoods, and wonderful green plants add some nice charm!
I sat and took my first break of the day here at the river crossing. I honestly thought this spot was amazing. I generally prefer big open vistas as opposed to intimate forest settings, but this really is a beautiful spot! Even better, I didn’t see or hear a single person during my entire time there!
From the river crossing, continue on the Travertine Springs Trail for another mile. The hiking is pretty easy still, but you will begin to gain elevation on this second half of the springs trail. One thing to note is very quickly after the river crossing, you will cross a gravel road. Make sure you quickly turn right, off this gravel road, and don’t continue along the road. I made this mistake and ran into a locked gate!
Just before the 5 mile mark of the day, you will hit another trail intersection. This time, the primarily singletrack springs trail hits the gravel road Saratoga Gap Trail. Turn sharply left onto the Saratoga Gap Trail!
The Saratoga Gap Trail:
You will have already begun the ascent back up to the trailhead by the time you reach the Saratoga Gap Trail, and that climb will continue. But, while you will be climbing here, it’s a very gentle incline!
I’m not really much of a fan of gravel road hiking, but here, the views are at least pretty awesome! The road follows an exposed hillside, and for probably a solid half a mile, you’ll have continuous unbroken views of the Santa Cruz Mountains!
Looking for huge old growth Redwoods? Head to Henry Cowell Redwoods State Park!
Don’t get too comfortable on the Saratoga Gap Trail, because after only ¾’s of a mile, you’ll begin the final section of this hike, the road walk back to the trailhead.
The Road Walk:
I didn’t realize this was coming, but most of the final 2 miles or so is on paved residential roads. It came as a bit of a surprise when I saw a sign signaling the end of the state park, and the new rules for hikers through the neighborhood!
The houses here are pretty interesting to look at. I imagine many of them are off grid and are largely self reliant, so that was at least interesting. However, road walking isn’t really the reason I go hiking, so it became a bit of a slog just trying to hustle back to the trailhead.
There’s a few turns to make and bends to follow to make it back to the highway, so I recommend having a map while hiking through here. There are quite a few signs so you should be fine without, but I got a bit confused at times.
Almaden Quicksilver is really close and has more great hiking outside San Jose!
After maybe a mile and a half walking through the neighborhood, you’ll hit a sign saying hikers must take the trail left while vehicles may continue on the road. I don’t know if you actually have to, but rather than risking confrontation, I hopped back onto the single track for the final few hundred yards. The trail here was actually really pretty, and you have to climb a bit more so might as well hike!
After a very short walk, you’ll rejoin the Skyline to the Sea Trail, and once again encounter the highways. Once you run into highway 9, follow it uphill to 35, cross, and you’re back at the parking lot, right where you started!
Topdown Lifestyle Rating: 7/10
This is a decent hike for those looking to explore the Castle Rock area or the broader Santa Cruz Mountains, but it does not make the highlight list for the range. While little about this hike is terrible (though the traffic and gun noise and road walking are a bummer), there isn’t anything that makes it great either.
If you live in the area and have hiked the Santa Cruz Mountains extensively, then sure, it’s worth checking out this trail, but there are lots of other hikes I would do first!
Pros:
- Easily accessible
- Nice views
- Little traffic
Cons:
- Views are limited to short sections of trail
- Road walking
- Traffic and shooting noise
- No wow moments
Alternative Hikes:
Henry Cowell Redwoods State Park
When To Hike The Big Basin and Castle Rock Loop:
While you certainly could visit Castle Rock in summer, it’s going to be hot. For me, I don’t love the heat, so I would probably try to avoid this area in the peak of summer, or if I did visit, I would be sure to go in the morning or the evening.
Castle Rock is a great place to visit any time from fall through spring if you don’t love the heat. Expect warm, pleasant temperatures in spring and fall and cooler days in winter, but in the sun it’ll probably still feel warm! And honestly, summer isn’t bad.
Castle Rock benefits from the rain shadow created by the Santa Cruz Mountains, so it is quite dry throughout the year. Most rain will fall from December-March, but many days in that time will still be sunny. The dry does create fire risk later in the year, especially from August to November.
Links For Further Reading:
Big Basin and Castle Rock Loop – California | AllTrails
