I thought this book was very interesting. Notice that the word "prison" in the title is plural, so it talks about more than 1 prison, and I really enjoyed that. I love how the setup is. It has a brief summary of the place, then it has when it was open, how many inmates were there, famous inmates, other names, and where it is located. To top it off, it has a picture of the whole place. I liked how if it was a special prison (like Alcatraz) it had more details, pictures, and words. I recommend this for anyone into scary stuff or history. I like both, so this was the perfect fit for me.