Garland Ranch Regional Park. Miles of trails through maple-filled canyons and woodlands. Dogs can swim in ponds and the Carmel River. You'll find a variety of trails throughout this 4,500 acre park including some that are flat (along the valley floor) and others that ascend to 2000ft. Note that horses are allowed on many trails so your dog has to be "equine-friendly." Dogs are allowed off-leash but should be under owner control.
Castro Valley Community Park, also known as the Castro Valley Community Center (CVCC) is Castro Valley's biggest park and offers the most amenities, it sure didn't look like this when I lived there. There was a fighter jet in the playground.
Happy Hollow Park & Zoo- Happy Hollow has a small zoo and a small amusement park for the price of one ticket. The amusement park features all you can ride carouselles, as well as a train and a puppet show. Happy Hollow is perfect for kids 2 to