Stretching along San Leandro's bay shoreline, Marina Park is a great place to jog, bird watch, host a barbecue and more. Picnic areas can be reserved from April 1 through Oct. 31, including three large group sites. There are also two playgrounds, two sand volleyball courts and a long, flat, grassy field. A mile-long fitness trail parallels the bay. Clear days here offer excellent views of the Santa Cruz Mountains, San Francisco, and the planes landing and taking off from nearby Oakland International Airport.