| 7 Springs Loop | | Fremont Older | San Jose | CA | |
| 99 Bottles | | Scotts Valley | Scotts Valley | CA | |
| A4 Pond Loop Trail | | Don Edwards San Francisco Bay National Wildlife Refuge | Fremont | CA | |
| Acorn Trail | | Arastradero Preserve | Palo Alto | CA | |
| Adobe Creek Trail | | Palo Alto | Palo Alto | CA | |
| Advocate Tree | | Nisene Marks State Park | Aptos | CA | |
| Agua Caliente Trail | | Ed R. Levin County Park | Fremont | CA | |
| Alameda Creek Trail North | | Fremont | Fremont | CA | |
| Alamitos Creek | | Almaden Quicksilver County Park | San Jose | CA | |
| Alamo Creek Trail | | San Ramon | San Ramon | CA | |
| Alder Spring | | Monte Bello Open Space | Palo Alto | CA | |
| Alexander Zuckermann Memorial Trail | | East Bay Waterfront | Berkeley | CA | |
| Almaden Trail | | Calero County Park | San Jose | CA | |
| Almeria Trail | | El Granada | El Granada | CA | |
| Alpine Road | | Monte Bello Open Space | Palo Alto | CA | |
| Alpine Warm-up | | Arastradero Preserve | Palo Alto | CA | |
| Alviso Slough Trail | | Don Edwards San Francisco Bay National Wildlife Refuge | Fremont | CA | |
| Amphitheater Trail | | Sugarloaf Mountain | San Mateo | CA | |
| Ancient Oak | | Monte Bello Open Space | Palo Alto | CA | |
| Anna Jean Loop | | Anna Jean Cummings Park | Soquel | CA | |
| Anza Esplanade | | The Presidio of San Francisco | San Francisco | CA | |
| Apay Way | | Coyote Hills Regional Park | Newark | CA | |
| April Trail | | Almaden Quicksilver County Park | San Jose | CA | |
| Aptos Rancho Trail | | Nisene Marks State Park | Aptos | CA | |
| Aquarius Road | | Joseph D. Grant County Park | San Jose | CA | |
| Aquila Loop | | Alum Rock Park | San Jose | CA | |
| Arguello Parking Lot to Road | | Arguello Park | Menlo Park | CA | |
| Arguello Trail | | Arguello Park | Menlo Park | CA | |
| Arguello Trail to Vista Point | | Arguello Park | Menlo Park | CA | |
| Arguello Traverse | | Arguello Park | Menlo Park | CA | |
| Arrowhead Loop Trail | | Coyote Valley Open Space Preserve | Morgan Hill | CA | |
| Arrowhead Picnic Lookout | | Coyote Valley Open Space Preserve | Morgan Hill | CA | |
| Arrowhead Topper | | Coyote Valley Open Space Preserve | Morgan Hill | CA | |
| Arroyo Seco | | Santa Cruz | Santa Cruz | CA | |
| Arroyo Valle | | Shadow Cliffs | Pleasanton | CA | |
| Artemisia | | Leona Canyon Regional Open Space Preserve | Oakland | CA | |
| B-Line | | Highlands | San Mateo | CA | |
| Baccardo | | Alum Rock Park | San Jose | CA | |
| Baccharis | | Redwood Regional Park | Oakland | CA | |
| Back Singletrack | | Sycamore Grove Park | Livermore | CA | |
| BackSide | | California | Pleasanton | CA | |
| Backsideline | | Pleasanton Ridge | Pleasanton | CA | |
| Bald Mountain Trail | | Sierra Azul Open Space Preserve | Los Gatos | CA | |
| Bald Peaks Trail | | Calero County Park | San Jose | CA | |
| Baldwin Loop | | Wilder Ranch | Santa Cruz | CA | |
| Barlow Road | | Sierra Azul Open Space Preserve | Los Gatos | CA | |
| Barn Trail | | San Jose | San Jose | CA | |
| Bass Cove | | Anthony Chabot Regional Park | Castro Valley | CA | |
| Bass Lake Trail | | Joseph D. Grant County Park | Dinuba | CA | |
| Bathroom | | Diablo Foothills Regional Park | Walnut Creek | CA | |
| Bathroom Connector | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Battery East Road | | Sausalito | Sausalito | CA | |
| Bay Area Ridge Trail | | Mission Peak Regional Preserve | Fremont | CA | |
| Bay Area Ridge Trail | | Mission Peak Regional Preserve | Fremont | CA | |
| Bay Area Ridge Trail | | Saratoga Gap Open Space Preserve | Saratoga | CA | |
| Bay Creek Trail | | Morgan Territory Regional Preserve | Danville | CA | |
| Bay Laurel Trail | | Arastradero Preserve | Palo Alto | CA | |
| Bay Leaf Trail | | Pleasanton Ridge | Pleasanton | CA | |
| Bay Trail | | The Presidio of San Francisco | San Francisco | CA | |
| Bay View Trail | | Fremont Older Open Space Preserve | Saratoga | CA | |
| Baylands Bike Path | | Don Edwards San Francisco Bay National Wildlife Refuge | Fremont | CA | |
| Bayview | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Beach Connector Trail | | Wilder Ranch | Santa Cruz | CA | |
| Bella Vista | | Monte Bello Open Space | Palo Alto | CA | |
| Bench Side | | Coyote Valley Open Space Preserve | Morgan Hill | CA | |
| Berkeley Drop Trail | | Glen Canyon Park | San Francisco | CA | |
| Berkeley Way Trail | | Glen Canyon Park | San Francisco | CA | |
| Bernal Hill | | Santa Teresa County Park | San Jose | CA | |
| Bernal Trail | | San Francisco Bay Area | San Jose | CA | |
| Bernice Rodgers Way trail | | Golden Gate Park | San Francisco | CA | |
| Berry Trail | | Waterdog Lake Park | Belmont | CA | |
| Big Bear | | Alum Rock Park | San Jose | CA | |
| Big Trees (Climbing Path) | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Big Trees (inner) | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Big Trees (outer) | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Bike Path | | Rancho San Antonio Open Space Preserve | Los Altos | CA | |
| Bill Kiefer Trail | | Las Trampas Regional Park | Alamo | CA | |
| Bishop Road Cutoff | | El Granada | El Granada | CA | |
| Bishop's Walk | | Joaquin Miller Park (JMP) | Oakland | CA | |
| Black Hawk Creek Road | | Mount Diablo State Park | Danville | CA | |
| Black Hawk Ridge Road | | Mount Diablo State Park | Danville | CA | |
| Black Hawk Shoot | | Mount Diablo State Park | Danville | CA | |
| Blue Blossom | | El Corte de Madera Creek Open Space Preserve | Redwood City | CA | |
| Blue Oak Knoll | | Pleasanton Ridge | Pleasanton | CA | |
| Blue Oak Knoll | | Pleasanton Ridge | Pleasanton | CA | |
| Blue Oak Trail | | Morgan Territory Regional Preserve | Danville | CA | |
| Bluff Connector | | Wilder Ranch | Santa Cruz | CA | |
| Bo Gimbal | | Monte Bello Open Space | Palo Alto | CA | |
| Boardwalk Trail | | Glen Canyon Park | San Francisco | CA | |
| Bobcat | | Wilder Ranch | Santa Cruz | CA | |
| Boccardo Loop | | Alum Rock Park | San Jose | CA | |
| Bog Trail Connector | | San Bruno Mountain Park | Brisbane | CA | |
| Bollinger Canyon Trail | | Las Trampas Regional Park | Alamo | CA | |
| Bollinger Creek Loop | | Las Trampas Regional Park | Alamo | CA | |
| Bonhoff Trail | | Joseph D. Grant County Park | San Jose | CA | |
| Bonus Hill | | Arastradero Preserve | Palo Alto | CA | |
| Bottom Clencher | | Sugarloaf Mountain | San Mateo | CA | |
| Bottom Clencher Alternate | | Sugarloaf Mountain | San Mateo | CA | |
| Boulders Trail | | Glen Canyon Park | San Francisco | CA | |
| Bound Back | | Del Valle Regional Park | Livermore | CA | |
