Explore the most popular mountain biking trails in Sierra Azul Open Space Preserve with hand-curated trail maps and driving directions as well as detailed reviews and photos from hikers, campers and nature lovers like you.

Only hiked to Priest rock and back on Kennedy because it was very hot, most of the hike is in the open/sun, and I didn’t want to run out of water for my pup and I. Four miles up hill... saw a rattlesnake on the way up and a fox near the top. Lots of sparrows and butterflies along the way. Irises are blooming now. Bring more than one canteen if you’re planning to hike this in the summer!

The parking is limited and not the easiest to back out of if there’s other cars parked.

1 month ago

Second time today - same gorgeous hike. First time was right after the trail opened. The newly installed gates at the Hicks road intersection and Bald Mountain parking lot open automatically at 7 am and stay open until after half hour past the sunset.

1 month ago

Hike was pretty easy. When you start your hike and you’re in the woods, there’s this abandoned blue buggy down the hill. Looks super creepy and there was barely anyone on the trail also. Views were alright. I traveled far for this hike but it was eh.

Hiked 4.7.18, right after bay area storm, and pleased that trail was very passable, a little muddy in places, but not much. parking, restrooms were very convenient, trail was very nicely graded, creeks, shades, wildlife (I saw deer, chipmunks, bobcat, and lots of birds), wildflowers, and great views. Very pleased with today's hike.

It’s a nice trail. Gets quite steep at a few spots. That coupled with the total length can make it a hard one. If you’re a regular hiker this should be a nice 4 hour workout. Not too easy but definitely not crazy hard either.
Views up top are nice. Nothing much to see along the way.

hiking
1 month ago

Nice cool walk

2 months ago

IMPORTANT NOTE: the directions take you to the crest of the trail, which is fine if you'd rather go downhill first. if you want to start at the trough as shown in the map, the parking lot you want is the "Sierra Azul open space preserve at Mt. umunhum road parking lot" on Google maps. Great hike, fantastic views of the South Bay.

hiking
2 months ago

Not a strenuous hike. But it’s beautiful. On the weekends parking can be a hassle so I’d recommend getting there early. I’d say the hardest part of the hike is the end.

2 months ago

Spectacular 360 degree view of the Bay Area in top! I could see the Bay Bridge, Lick observatory, and Santa Cruz mountains. The hike itself was moderately easy with lots of shades. I spotted some melting snow near the top. Overall, great hike. Recommend going on weekdays or going early on weekend because parking is limited. I started from the second parking lot for a total of 7.7 miles hike

2 months ago

moderate uphill, not much of a view at the top.

on Mount Umunhum

hiking
2 months ago

I’m so glad they opened this preserve up after so many years of being closed. Great hike with decent amount of shade, but there are plenty parts of the hike that are not shaded - so dress in layers would be my advice. Once at the top, it can get quite windy but the views are beautiful. For those who cannot hike the distance, there is a road for cars that will lead you to the top as well. Oh, on a side note, I did come across a tarantula cruising along some rocky path at the very top! So watch your step!

Not the most variety but fantastic views, lots of birds! And because it’s a fire trail, easy to walk with a companion.
My 22 year daughter and I made it to the top but I found it a hard hike. The rolling ridge at the top was a bit daunting for me but worth the trip.
Round trip with a lunch break for us was about 5 1/2 hours.

IMPORTANT FOR DOGS: the last part of ascent (last 500m) does not allow dogs. My wife stood with my dog while I was checking this section. That is a shame because this is the section where you get the best views of San Jose. Definitely hard but not exhausting. Some parts get fairly steep.

Hiked 2-10-18. Enjoyed the walk up, noting the beautiful madrones, oak, and manzanita trees. Also got to a see a Bobcat! Trail was nicely shaded with great views of San Jose. I also enjoyed the company of a new friend Peter. Cheers.

hiking
3 months ago

Xcellent views limited parking moderate difficulty.

hiking
3 months ago

Get there early (8AM) as lots are small and where you park depends on how far you want to hike if your intention is to get to the building. First parking lot - round trip is about 16-17 miles. Second parking lot - 7.5 miles. Third parking lot - a few yards. You can alternatively park in some turnouts, but might be problematic walking on the two lane road.

Trail itself has some nice views. The main trail to Mt Umunhum is very razor thin to have mountain bikers on the trail. Three people can hardly fit side-by-side, so who thought it was a good idea to allow bikers? Also, when they stop, there is hardly any space to pass them.

This has a lot of uphill hiking- it’s not just uphill out and downhill back, so be prepared! Great training!

Excellent trail gradual slope and great view of San Jose valley and surrounding mountain ranges from the top.

4 months ago

Trail is a double track gradually climbing to the summit. There is about a 50/50 mix of trees and unshaded areas. Well maintained and beautiful trail. Took me 4 hours to complete, not including time hanging out at the top. There are bathrooms at the trailhead and at the summit. You can also skip the hike all together and drive all the way to the summit where there is a parking lot. The views at the top are amazing. You can see the entire valley...Mt Diablo, Mt Tam, Mt Hamilton..from Mt Unumhum!

hiking
5 months ago

Only about 15 parking space in trail head. You may go weekdays or get there before 8 AM on weekends. The summit has about 56 parking space. The good news is those people who just sight seeing on the summit won't stay long. So you may wait patiently on summit parking lot on weekends to get space. Then hike down and back to summit. The near 360 degree view on summit is gorgerous. You may eat sandwich and rest for half hours on summit and continue your hiking. in general, it's an easy trail, the elevation gain is smooth out over 3.5 miles trail. except for the last section near the umunhum summit, the trail is mostly shady.

Monday morning hike so trail wasn’t busy. Great local hike if you can’t get away from the area.

hiking
6 months ago

hiking
7 months ago

After being recommended to hike Mt Umunhum since its opening in September 2017, I had been waiting to get out there.

The trail seems very well maintained and has mile markers along the way right up till the 3 mile mark after which you are led up to the summit (approximately another 1 mile), with gorgeous panoramic views along the way. The trail is shaded throughout and in-spite of being out and back (which I generally do not prefer), there is still a lot to see to keep you busy both ways.

If it interests you, spread across the trail are informative boards explaining the history of the mountain. There are also a few scenic lookouts. The summit is accessible via road and has restrooms.

hiking
7 months ago

An enjoyable trail to an interesting historical artifact. Characteristics:

1. Parking can be limited. We spent half-an-hour on a Sunday early afternoon waiting for one parking spot among 20-ish at the Bald Mt. TH parking lot until one freed up. YMMV depending on the day and time.

2. As of early October 2017 (read: prior to its first rain season), the Mt. Umunhum trail is extremely well-graded and groomed. But as a primarily dirt 1.5 track (everything but the last 0.2 miles to the summit was designed and designated as a multi-use trail), it can be a bit dusty. It is a very fast trail to crank-out a bit of miles/elevation (on foot or on wheels), and noticeably easy on the feet and knees. But as somebody who used to be an expert-level MTBer, the trail as it currently stands would not be very attractive due to its high foot traffic and completely sanitized nature (read: long, dirt sidewalk on a mild incline).

3. The trail is more shaded along the route than you might imagine. It can also be windy, esp. at the summit.

4. There is no potable water at either the Bald Mt. TH nor the Mt. Umunhum summit. I am told there isn't any at the general-parking/picnic/restroom facilities just off the summit as well. I was also told that there are no plans to run water up there. You need to bring yourself every bit you will need.

5. The Mt. Umunhum summit is accessible by car (next-to-the-site parking is available for handicap placards, regular parking is just off the summit a short distance away), so there will be lots of people visiting the site that way. You're not reaching some secluded waterfall to introspect and wax philosophical. There will be lots of people with kids, taking phone panoramas. That's all good, as long as your expectations are in-line.

DY

hiking
7 months ago

If you're hiking to the top, give yourself enough time to hike back down by 7:35pm or else you'll find yourself running down hill for almost 4 miles nonstop racing against the clock :)

hiking
7 months ago

Nice trail recently grade. Great views along trail and at the top. Can see from SF to Gilroy. Nice new grounds, viewing area and restrooms at top. The Mid Peninsula Open Space did a great job opening the park

Definitely worth doing

hiking
7 months ago

Breathtaking views await you in the recently opened Mt. Umunhum trail. A 7.9 mile out and back hike from Bald Mountain Parking lot to the summit, the place is full of history from Native American times to Cold War and more.

Detailed blog: http://shompens.com/canvas/1506037390153

This trail opened to public on Sep 17 2017 after 1.5 years and $25 million dollar restoration effort.

This is nice moderate 7.4 miles out and back trail.
The best parking spot is Bald Mountain parking spot 1.6 miles up mt. Umunhum road and Hicks road intersection. There are about 10 spots + 4 on the sides. Gets filled up early so go there before 7:30 am to get a spot.

The views are spectacular and once on the top, you will be rewarded with gentle breeze.

you will enjoy every minute

A great hike to finish this trails in the area for the Sierra Azul Ridge! Trails open to public officially 2017 September 18!

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