Alcatraz derives from the name Spanish explorer Juan Manuel de Ayala gave to one of the three islands in San Francisco Bay, “Alcatraces,” probably referring to the “strange birds” or “pelicans” he saw on it. Its strange name (its meaning still debated) is appropriate, given The Rock’s unique history as a federal penitentiary, but as our guide noted, some of the island’s truly unique artifacts are its gardens and the stories behind them.