I have always liked the Liberty Hotel in Boston since it opened in 2007. The Liberty is one of the bestter adaptive reuse projects of this century, as it turned Boston's nortorious Charles Street Jail into a five-star hotel. Here is a video tour of the hotel in 2017.

The exterior of the old, medieval jail is still intact. It always had a grim and depressing aspect, built next to the Massachusetts Eye and Ear Infirmary, on the grounds of the Massachusetts General Hospital. The hotel is really imaginative, and makes clever use of the existing architecture. The old jail has been used in a couple of movies, and I think it even appeared once in a Spenser for Hire episode.