Meet at the designated time at the Sausalito ferry landing in downtown Sausalito. If you're arriving from San Francisco, you can take the ferry to Sausalito from the San Francisco Ferry Building at the foot of Market Street.
Head to Fort Baker, a former military base situated at the base of the northern span of the Golden Gate Bridge. Following the bayshore, get close views of the North Tower of the bridge, then wind underneath the span via a car-free road. The short trail leads to Battery Spenceer, an overlook high above the bridge deck and the entrance of the Golden Gate. On foggy days, the span is shrouded in ocean mists. On clear days, you can see San Francisco Bay, the city skyline, Alcatraz Island, the Marin Headlands, and perhaps the Farallon Islands in the distance.
Have time to eat a picnic lunch (not included) then loop back down the hill to return to the Sausalito Ferry Terminal where your tour ends.