Overview
The Marin Headlands pack more into a single outing than almost anywhere else in the Bay Area: a black-pebble beach where kids hunt for jade, jasper, and carnelian; WWII concrete bunkers that kids can actually climb on; a free wildlife rehabilitation center with live seals and sea lions; and coastal trails with views that stop adults mid-sentence. Rodeo Beach is dark sand made from colorful metamorphic rock — not imported sand, but the actual geology of the headlands — and at low tide the south end opens into tide pools. This is a half-day at minimum and most families end up staying longer.
How to Do It
From Highway 101, take the Alexander Avenue exit (just north of the Golden Gate Bridge). Go right at the stop sign, follow Alexander Avenue back under the freeway, then turn left on Danes Drive. You'll hit the Baker-Barry Tunnel — it's one lane and alternates directions, controlled by traffic lights, so expect a wait of up to 5 minutes. Follow Bunker Road all the way to the end; it dead-ends at the Rodeo Beach parking lot and Fort Cronkhite. The main parking lot at Rodeo Beach is free and sits right at the beach — it's the most convenient spot. On busy weekends it fills by 9:30 AM; overflow parking is along Bunker Road, which adds a flat 10–15 minute walk to the beach. Start at Rodeo Beach and let kids dig through the pebbles and check the tide pools on the south end. From there, Battery Mendell is a 10–15 minute walk up Fort Barry Road toward the Point Bonita YMCA — it sits high above the beach with two 12-inch disappearing gun emplacements that kids can climb into and around. Battery Alexander (picnic area, mortar pits) and Battery Wallace (literally built into the hillside) are both worth looping through. The Marine Mammal Center is a short walk from the Rodeo Beach lot in Fort Cronkhite — free but requires a timed ticket reserved in advance at marinemammalcenter.org.
Tips & Tricks
Check a tide chart before you go. Low tide on the south end of Rodeo Beach opens up tide pools and exposes more of the colored pebble beach for gem-hunting; high tide pushes you up onto the coarser upper beach. The pebble hunting is the single biggest hit with kids under 8 — bring a small bag or container so they can carry their finds. The Baker-Barry Tunnel is one-way and the wait can feel longer than it is; if traffic is backed up, the light will cycle in a few minutes. Weekend mornings before 9 AM give you an almost empty headlands; post-noon on summer weekends it gets heavy with visitors. The Marine Mammal Center requires advance tickets even though admission is free — book at marinemammalcenter.org before you leave the house. The Nike Missile Site SF-88L (the only restored Nike missile site in the country) is open Thursday through Saturday noon to 3 PM — you can watch an actual Hercules missile raised from its underground storage on guided tours; first Saturday of each month is the Nike Veterans Open House. Dress as if it's 10 degrees colder and 20 mph windier than wherever you started from in the East Bay or Peninsula. Even on clear summer days, the ridge and beach can be fully fogged and cold.
Planning
The park is free and open sunrise to sunset year-round. Parking at Rodeo Beach is free. The Marine Mammal Center is free but requires timed tickets reserved at marinemammalcenter.org; open daily 10 AM to 4 PM. Nike Missile Site is free, open Thursday through Saturday noon to 3 PM; call (415) 331-1540 to confirm hours, as inclement weather closes it. Bring layers for everyone (wind shell, fleece, hats), sturdy shoes with actual grip for the bunker trails, snacks and water (there is no food for sale anywhere in the park), and a bag for rock collecting. Restrooms are available at the Rodeo Beach lot and near the visitor center. Best months are April through October — summer fog keeps temperatures manageable; November through March can be genuinely cold and the trails get muddy. Minimum useful age is around 3 years old for the beach and bunker scrambling; the tide pool walk is slow-paced and fine for patient 3-year-olds. Kids 5 and up get the most from the full experience including the bunker history and missile site.