Golden Gate Bridge
The Golden Gate Bridge — 2.7km of International Orange steel across the mouth of the Bay, completed in 1937 — is the most photographed bridge on earth and still the most dramatic single piece of infrastructure in North America. Walking or cycling across is free and one of the finest urban experiences available on the continent: the Bay on one side, the Pacific on the other, the city behind you, the Marin Headlands ahead. The best viewpoints: Battery Spencer in the Marin Headlands (north side, 15 minutes from the bridge toll plaza by car or rideshare — the bridge and SF skyline together), Baker Beach (south side, sandy beach at the foot of the bridge — often foggy but extraordinary when clear), and the Welcome Center viewpoint on the south side plaza. Allow 2–3 hours for the bridge walk and viewpoints.