The National Library of Finland (Finnish: Kansalliskirjasto, Swedish: Nationalbiblioteket) is the foremost research library in Finland.
In addition to being the most important of the libraries of the University of Helsinki, the National Library is responsible for storing the Finnish cultural heritage. By Finnish law, the National Library is entitled to receive copies of all printed matter, as well as audiovisual materials excepting films, produced in Finland or for distribution in Finland.
The National Library is located in a library complex in the heart of Helsinki, right by Senaatintori square. The oldest part of the complex, designed by Carl Ludvig Engel, dates back to 1844. The newer extension Rotunda dates to 1903. The bulk of the collection is, nonetheless, stored in Kirjaluola (Finnish for Bookcave), a 57,600-cubic-metre (2,030,000 cu ft) underground bunker drilled into solid rock, 18 metres (59 ft) below the library. The library collections, the largest in Finland, comprised about 109 kilometres of shelf space. The collections included a total of some three million books and periodicals. Approximately 7.6 million pages of digitised material were viewed over the web. Some 224 million files were harvested for the Finnish Web Archive, which currently contains a total of 718 million files.