I think every book-lover person knows the feeling: getting lost in a beautiful, old library, collecting way more books than you could possibly read, and spending hours with your favorite authors and stories. This is what I used to do as a student in Szabó Ervin library, and it is still in my top 5 places in Budapest. This is the main library, with thousands and thousands of books in Hungarian and other languages.
The building itself consists of two parts: a newer one from the socialist era, and an older one that was built in 1889, in a neo-baroque style. It is basically a palace, and all the wallpapers, fireplaces, furniture and inlaid wooden coverings look the same as they did a hundred years ago.
Anyone can get a free pass into the library at the information desk, and can go inside to look around, read some books or magazines.
Another reason for going there is that they also have a nice cafeteria right behind the entrance, with even nicer prices.