The French National Library opened in 1996 with a futuristic design by Dominique Perrault (a quartet of 24-story towers evoking the look of open books); this is the last of the grands projets of the late François Mitterrand. It boasts the same grandiose scale as the Cité de la Musique and houses the nation's literary and historic archives; it's regarded as a repository of the French soul, replacing outmoded facilities on rue des Archives. The library incorporates space for 1,600 readers at a time, many of whom enjoy views over two levels of a garden-style courtyard that seems far removed from Paris's urban congestion.
This is one of Europe's most user-friendly academic facilities, emphasizing computerized documentation and microfiche -- a role model that will set academic and literary priorities well into the future. The public has access to as many as 180,000 books, plus thousands of periodicals, with an additional 10 million historic (including medieval) documents available to qualified experts. Though the appeal of this place extends mainly to serious scholars, a handful of special exhibits might interest you, as well as concerts and lectures. Concert tickets rarely exceed 15€; a schedule is available at the library.