Which Pretty Little Liars Characters Have Stayed at Radley Sanitarium?

Radley Sanitarium is a very creepy mental institution that many characters on Pretty Little Liars have unfortunately called home. Thanks to mental breakdowns after traumatizing situations, several of these characters have been medicated out of their minds in the institution. Have a hard time keeping track of who stayed there? That's understandable. Here are all the characters who have been patients at Radley, at least, those that we know about. Take a look, and if you haven't already, check out the questions we need answered after this week's premiere.