trail running


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mountain biking

nature trips



As described by the Midpeninsula Regional Open Space District: "Overlooking the town of Los Gatos and the south bay, Sierra Azul Open Space Preserve is the District's largest preserve, encompassing over 17,000 acres of mostly rugged and steep terrain. The environment of Sierra Azul is strikingly varied. One can visit serpentine grasslands, hard, rocky, and steep chaparral, dense stands of bay trees, or quiet, shaded oak woodland forests. For the more hardy explorers, there are deep ravines and riparian corridors, some containing seasonal or year-round water flow. Wildlife is abundant in Sierra Azul. The entire Preserve is prime mountain lion habitat and also provides homes for deer, bobcats, coyotes, and many other species of animals. Sierra Azul ("Blue Range") is a true wilderness area, yet surprisingly close to the urban areas of the South Bay, making it a popular destination."

Only a small amount 'street' parking; and maybe not strictly legal. Generally easy trail and quiet.

It's nice & quite to hike this place

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.

11 days ago

Xcellent views limited parking moderate difficulty.

19 days 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!

Beautiful trail and views!!

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

1 month 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!

2 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.

Good elevation gain to get you some good exercise. Mostly shaded except at the top. Great views of the reservoir towards the end. Small parking area on roadside at the trail head.

Beautiful hike

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

3 months ago

4 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.

4 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.


4 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 :)

4 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

4 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.

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