The Klementinum library was voted as the most beautiful library showing off amazing Baroque architecture. First opened in 1722 with over 20,000 books, it used to be the third largest Jesuit college in the world. The ceiling frescoes were painted by Jan Hiebl. In 1781, director Karel Rafael Ungar established Biblioteca Nationalis, a collection of Czech language literature. Some of the rare historical books from this collection have been sent to Google for scanning and will eventually be available on Google Books.

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