Having been created in 1973 the British Library is surprisingly young compared to equivalent libraries in other countries. Holding over 150 million items, The British Library is one of the world's most significant research libraries. However, The Guinness Book of World Records lists the Library of Congress as the 'Largest Library'(based on the shelf space the collection occupies, the Library of Congress fills about 850 km while the British Library,reports about 625 km of shelves). However the British Library is the owner of 150 million items compared to The Library of Congress with only 130 million items. More than that, The British Library adds an average of 3 million items a year proving to be one of the most visited places in London.