One way to determine where to hike is to first decide which region you favor. The San Francisco Bay Area is comprised of the East Bay, North Bay, Peninsula, South Bay and San Francisco. Here's a little info on each:
- East Bay. This section of the Bay Area lies across the bay from San Francisco and the Peninsula. Its most populous city is Oakland; neighboring Berkeley is famed for its university. Two of its popular hiking areas are Redwood Regional Park and Mount Diablo State Park. The 1,800-acre (728-hectare) Redwood Regional Park was extensively logged in the 1800s, but has been replanted and features a lush forest of 150-foot (46-meter) coast redwoods. The park features a few main trailheads, such as Skyline Gate Staging Area [sources: East Bay Regional Park District, Bay Area Hiker]. Mount Diablo is known for its views; geographers say hikers can actually see more of Earth's surface from its peak than any other peak on the planet, except for Africa's Mount Kilimanjaro. Although most visit this oak-chaparral-grassland park via auto, there are several miles of trail to ramble [source: California Department of Parks and Recreation].
- North Bay. This section lies north of San Francisco and includes Marin, southern Sonoma, southern Napa and Solano Counties. Head to Armstrong Redwoods and Sugarloaf Ridge state parks for prime hiking. The former has several trails ranging from oh-so-easy to gaspingly difficult, plus accessible pathways and, of course, stunning coast redwoods [source: California Department of Parks and Recreation]. The latter features 25 miles (40 kilometers) of trail passing through oak woodland and chaparral, and contains the headwaters of Sonoma Creek [source: California Department of Parks and Recreation].
- Peninsula. The Peninsula extends south from San Francisco, across San Mateo County and the northern slice of Santa Clara County. You can't miss the 3-mile (4.8-kilometer) hike at Año Nuevo State Park, where large numbers of northern elephant seals gather. Hikers can watch males battling it out for a comely female seal, and females birthing on the beach. During breeding season (Dec. 15-March 31), you're only allowed in the park on a guided walk [source: California Department of Parks and Recreation].
- South Bay. San Jose is HQ of the South Bay, which lies south of both the Peninsula and the East Bay. At Uvas Canyon County Park, there are 6 miles (9.7 kilometers) of trail, including a 1-mile (1.6-kilometer) loop along Swanson Creek that will take you past several waterfalls. Some of the trails are quite easy, but those who want to challenge themselves can tackle the steep Nibbs Knob and Knobcone Point [sources: Santa Clara County Parks, Bay Area Hiker].
- San Francisco. This famous U.S. city is the region's namesake, and sits atop the peninsula. Head for the historic Presidio, a former Army post for three nations: Spain, Mexico, then the U.S. There are more than 25 miles (40 kilometers) of hiking trails here, including the Golden Gate Promenade [source: National Park Service].