Talk to San Francisco visitors, and they can’t recommend one of the top sights in San Francisco enough. Yet you can talk to locals and they’ve never been to Alcatraz Island, the remains of a historic prison.The ferry ride out is exhilarating and the views from the island are worth the trip, but it’s the tour that fascinates year after year. From its days as a maximum security prison to its time in the hands of Native American protesters who briefly reclaimed the island in 1969, Alcatraz has a colourful history. Walk among the ruins of the notorious prison and you feel chills, pondering what it might mean to live in isolation with the joys of the city so close and yet so far. The trip takes about three hours and the ferry ticket includes the audio tour. For a moonlit kick, consider touring at night.