Once home to America's most notorious criminals, Alcatraz is one of the world's most legendary federal penitentiaries. It is rumored to be haunted by infamous inmates like Al "Scarface" Capone and the "Birdman" Robert Stroud. So if you are looking for a scary Halloween activity, check out Alcatraz... at night.
The tour starts out like any other Alcatraz experience: souvenir photos, a ferry ride, and waiting in line to pick up the audio tour that will take you through most of the cellblock. But once it starts to get dark, the mood shifts. Nighttime visitors get to explore a part of the prison that's off-limits during the day: the hospital ward. It's open only for 30 minutes and even your audio tour doesn't include this abandoned area. It's all-around creepy.
If you can handle the nerves, stay on the island until the last ferry and experience the island like many haven't. Park rangers speak about famous inmates and demonstrate the automated cell door system. You are even free to wander the spooky halls on your own.