The Biblioteca Palatina, founded in 1761 by Philip of Bourbon, occupies a series of richly decorated rooms inside the Palazzo della Pilotta. The reading rooms — gilded shelves, frescoed ceilings, busts of philosophers — are a small architectural attraction in themselves; the collection includes incunabula, Hebrew manuscripts, the Bodoni archive, and Petrarch's own annotated copy of Virgil.
It functions as a working research library, but the historic main hall is open to visitors. Combined with the Galleria Nazionale and the Bodoni Museum, the visit easily fills a morning.