Most visitors to San Francisco snap their Golden Gate Bridge photos and move on, not realising there's a 335-acre park hiding just north of the span. Fort Baker, a decommissioned Army post in Sausalito, pairs big views of the bay with an unusual perk: a public pier where you can fish and crab without a licence, one of several such license-free piers in California.

The military history runs deep. After gold was discovered in 1848, the US Army fortified San Francisco Bay, and the headland that became Fort Baker hosted gun batteries and soldier housing. During World War II it formed part of the Harbour Defences of San Francisco, and later it served as a regional air defence headquarters overseeing Bay Area missile sites before the National Park Service took over around the turn of the 21st century. More than 25 historic Army buildings survive, and the post-to-park conversion mirrors what happened at the nearby Presidio.

Anglers drop lines for salmon, perch and the occasional leopard shark, plus red crabs, though it pays to check state regulations for seasonal limits first. Wildlife watchers get good value too: the endangered Mission Blue butterfly lives here, sea lions and harbour seals haul out near Horseshoe Cove, and the cove's small harbour rents boats and runs sailing lessons.

Two short hikes deliver classic Golden Gate views. The 1.17-mile Drown Road Trail passes historic sites with a self-guided phone tour, while the quarter-mile Chapel Steps Trail is a quick hit of bridge scenery. The flat Parade Grounds, once used for drills, make a good picnic spot afterwards. Families have a strong draw in the Bay Area Discovery Museum, with over 10 interactive Discovery Zones for kids up to age 8, including a Mud Kitchen and a River Run obstacle course. It opens Wednesday to Sunday from 10 a.m. to 4 p.m. (9 a.m. Saturdays), and tickets cost $25 for ages 1 to 64.

Getting there is easy. Walking across the Golden Gate Bridge from the Presidio side covers 4.2 miles and takes about 90 minutes. The 120 regional bus towards Strawberry Village costs $7.20 with Clipper or contactless payment and gets you close in under an hour, though there's roughly a 30-minute walk from Alexander Avenue and East Road down into the park.

If you want to linger, the old post has been partly converted into Cavallo Point, a wellness retreat regularly rated among the San Francisco area's best. Officers' quarters in Colonial Revival style now house guests, and two restaurants, Farley and Sula, occupy restored early-1900s buildings overlooking the bay. There's a cooking school, fort tours, painting classes, morning yoga and a meditation pool — at a price: weekend rates average around $777 a night.

Fort Baker suits a specific kind of traveller: history-minded walkers, families with young kids, and anyone who'd rather fish off a quiet pier than jostle for space at Fisherman's Wharf. It's a half-day trip that turns the bridge from the destination into merely the way in.