I’ve lived in San Jose for the past 12 years, and I’ve managed to scrape up a few outdoor trips that are worth doing in early spring and late fall. You’ll want to avoid doing these trips during the summer due to heat or people. People aside, the other mild nuances are Poison Oak and Ticks. Proper clothing and good outdoors habits can easily fix those. I’m sure there are other trips in the San Francisco Bay Area, but these in particular are located in the South Bay.
Henry Coe State Park
Located in the foothills of Morgan Hill, Henry Coe is HUGE. There are miles and miles of roads. I say roads because the trails are very few. Any hiking done in here is most likely going to be by dirt road. The terrain is tough, the roads go straight up, and then straight down. However, what can’t be beat is the wild flowers in the spring and the Madrone Manzanita. The Madrone grow to stupendous sizes and are a must see. Water is plenty during the spring, but if you come in the summer life sucks.
Once you get passed the main entrance out of Morgan Hill, there is the first zone which is all designated camping. Once you leave that zone, you get to go for it and pitch a camp wherever you deem dandy. That’s kind of fun, as long as its near water of course. One of the more notable campsites in the first zone is Willow Ridge Springs Camp. There are other campsites, but that one is the cool one as its still in the first zone, has water, and is far enough away where other backpackers don’t bother you. Its a nice overnight trip that covers a total distance of about 16 miles. There are some loops you can do for extended trips, and if you get into the back country during the wet season there is plenty of places you can swim.
For more information about Coe Park, see https://coepark.org/sites-backpacking.html
Castle Rock State Park
There is only one campground in Castle Rock State Park, and its barely 3 miles from the entrance. The campground is nice, and its on of the few places in the bay area you can legally have a campfire. But for backpacking, 3 miles is lame. However! There is a connector trail that starts in Sanborn County Park at the bottom of the hill in Saratoga. That adds a 6 miles to the trail and climbs 1500′ in 4 miles. Its a really nice pull and a great overnight training hike. Once you get to the top of the hill, you level out and move 2 miles north on a fairly level trail. At one point you cross the highway and you arrive at castle rock state park. From there you are about 3 miles from Castle Rock Trail Camp. Round trip you hike about 18 miles, and there is some serious elevation change. Its a nice challenge and some really nice scenery. There are plenty of backpackers on this trail so you’ll want to arrange your trip on non-holiday weekends or shoot for a weekday trip.
For more information: https://www.parks.ca.gov/?page_id=538
Big Basin State Park
There is a lot of notable trails in here, but the fun one specific to Big Basin is Berry Creek Falls Loop. Starting from big basin you drop down Skyline to the Sea Trail and you run right into Berry Creek Falls, its about a 5 mile hike. There is a quick elevation drop but it levels out a bit after the first 2 miles. Following that there is a steep 1 mile jaunt up to Skyline Trail Camp. It is an awesome little hike, but goes up fast and is quite a workout. From there you hike back Sunset Ridge Trail and loop back around to Big Basin HQ which is about 5.5 miles on that trail. This is another simple over night trip. During the trail hike from Berry Creek Falls, there are actually two more falls and the water has this interesting golden algae that grows in it. I believe it to be iron oxide algae, and the water is perfectly safe to drink (through filter of course). There is a slight metallic taste to it as well, obviously.
For more information: https://bigbasin.org/
Butano State Park
This small park still has old growth redwoods, so I imagine it looks very much as it did a century ago. There is a simple 11 mile loop with a trail camp half way through it. There is a 1300′ elevation gain, so its a nice overnight training hike. At the top of the hill near the camp there is an abandoned air strip.
For more information: https://www.parks.ca.gov/?page_id=536
Skyline To The Sea
This is the ultimate Bay Area hike. Some people do this hike in 2 days, some in 3. We did it in 4 days, whats the hurry ? Furthermore, using the Sanborn County Park connector trail, you can extend it to a 40 mile hike. Hiking from Castle Rock park entrance, you make your way down a steep trail towards Waterman Gap trail camp. Here the water is trucked in, but I always filter regardless. From there, its a nice climb back up about 1000′ in elevation and over a ridge, then back down towards Big Basin. From Big Basin you work down towards Berry Creek Falls, where its a fairly level hike to Waddell Beach. This is one of the nicest trails I have hiked, the forest floor is soft and moist. The air is clean, and it seems to stay moderate year round. The only downside of this trip, and its true with all of the above trips with the exception of Coe, is the outhouses are damn nasty. The State Parks in this area haven’t figured out the benefits of ash. A little bit of ash after each restroom use can make an outhouse a sweet place to sit.
For more information: https://en.wikipedia.org/wiki/Skyline-to-the-Sea_Trail