The Klementium library, is a beautiful example of Baroque architecture. The library was first opened in 1722 as part of Jesuit university. It houses over 20,000 books. The ceiling frescoes were painted by Jan Hiebl. In 1781, director Karel Rafael Ungar established Biblioteca Nationalis, a collection of Czech language literature.
Some rare historical books from the libraries collection have been sent to Google for scanning and will be made available on Google Books. The library is rare and little-known, so is it associated with several little-known facts: the Klementinum used to be the third largest Jesuit college in the world; recording of local weather began there in 1775 and has continued ever since; it is featured in a novel by famous Spanish-language writer Jorge Luis Borges.
More info: klementinum.com