Cody Simpson: 'Terror Behind The Walls' Haunted House!

Cody Simpson goes for a tour at the Eastern State Penitentiary in Philadelphia, Penn., on Saturday night (October 26).

The 16-year-old singer posed for some pics with a friend dressed up for the upcoming Halloween holiday.

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“Scariest haunted house I’ve ever been through. got to experience it with some real cool fans too <3 thanks @Q102Philly," Cody tweeted after the tour.

The penitentiary, which was opened in 1829, was designed to rehabilitate rather than punish. The first to implement solitary confinement, the inmates went insane and each Halloween, Terror Behind The Walls happens, the largest scarefest in America.