ScottFreeVT
We never miss up a chance to hike through this lovely spot. Every year when we visit our daughter and her family we come up here at least once to enjoy the trails and views. The scenery couldn't be more different than our native Vermont and just as lovely. It's only a few minutes west of downtown Palo Alto but a world apart. During the week you have the place pretty much to yourself but on the weekends you share it with other hikers, horseback riders and bicyclists. This time we even enjoyed watching 2 uni cyclists. But even then, you have lots of time alone as there are so many paths to choose from. There is a parking lot, information center and nice rest rooms. Maps of the trails are available. Come and have fun!
NapiliR
Plenty of parking, clean bathrooms (no porta potties here; real toilets/real sinks), several trails. The only downside is no shade in the summer. My hiking group hikes at a variety of parks, so we save Arastradero for cooler days. The hills are gentle and wide compared to many areas so it's great for beginning hikers or those rehabbing from injuries. We've seen coyotes and many varieties of birds. Easy to access off 280.
rootroofy
The best part of this preserve is that it exists! It is a great gift to the Bay Area that there are still natural places like this that aren't covered in tract home McMansions or research parks. Take water and sunscreen - there's not a lot of shade on these pretty hikes.
SandcruiserX
This is a user-friendly outdoor space; great for a gentle mountain bike ride or a sunny hike. There is a small interpretive center and the trails are reasonably well marked, though it is easy to get turned around.
JamshidV
You don't have to go far to get to this secluded place where you can hear birds and running water. Drive for few minutes from downtown Palo Alto, you will find this place tucked in a quiet road. My favorite trail is the long uphill trail passing the reservoir. Scenery is beautiful in all seasons, my favorite time for hiking is early spring mornings.
EBinLACA
I like this area a lot for a short hike in the hills with the dog (yes, dogs are allowed on leash). It's got hills, open space, woods, water, parking, restrooms, and several trails. And it's easy to get to from the Peninsula without having to drive into the mountains. Only problems are it's so close to I-280 that you can sometimes see and often hear the traffic. Also, the parking lot fills up on nice afternoons, so have a backup in mind if you can't get in.
weekendfurlough
Wanna get away from the suburban sprawl and see some nature theatre? Go here. I saw rabbits, hawks, coyote, and lots of great views. An excellent place to take the kids hiking so they can get some energy out.