1. Attica Prison: Attica, New York

One of the most famous correctional facilities in the United States, Attica Prison must be mentioned on this list. Whether a prison is “most dangerous” is usually determined by analyzing two different sources, who’s there and how have the inmates behaved. In terms of the first issue of who’s been imprisoned in Attica, you’d be surprised to find out that there’s a long line of deranged men who’ve spent time in upstate New York. Some of Attica’s more famous prisoners include Colin Ferguson (murdered six people in Long Island), Mark David Chapman (the guy who killed John Lennon), Sam Melville (the “mad bomb”), El Sayyid Nosair (1993 World Trade Center terrorist), Willie Sutton (notorious bank robber). These men make up a short list of New Yorkers that’d freak anyone out. In looking at the second source of analysis on how inmates behave, the answer is quite simple. Horribly. Prisoners were so sick of how they were being treated they decided to simply riot and riot hard in 1971. In the end 43 people were dead, including 10 civilians and officers and 33 inmates.