Kelley Park is a large and beautiful park in downtown San Jose, with lots of cool things to do, including the Japanese Friendship Garden, Happy Hollow Zoo, History Park, and the disc golf course. The disc golf course winds around through an old walnut orchard with a nice trail around it, perfect for a <1 mile stroll.
You're looking for a camo'd preform container hidden a few feet from the trail. The trail is close to the disc golf course, so you might have to wait out some "golfers", but they move quickly. If you park in the Kelley Park parking lot, there's a $6 fee, but you can find free street parking on the other side of Senter Road.
Kelley Park is open daily from 8:00am to one half hour after sunset. Happy hunting!